added full udhcp integration

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diff --git a/networking/udhcp/README b/networking/udhcp/README
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+udhcp server/client package readme
+-------------------------
+
+The udhcp server/client package is primarily geared towards embedded
+systems. It does however, strive to be fully functional, and RFC
+compliant.
+
+udhcp server (udhcpd)
+--------------------
+
+The only command line argument to udhcpd is an optional specifed
+config file. If no config file is specified, udhcpd uses the default
+config file, /etc/udhcpd.conf. Ex:
+
+udhcpd /etc/udhcpd.eth1.conf
+
+The udhcp server employs a number of simple config files:
+
+udhcpd.leases
+------------
+
+The udhcpd.leases behavior is designed for an embedded system. The
+file is written either every auto_time seconds, or when a SIGUSR1
+is received (the auto_time timer restarts if a SIGUSR1 is received). 
+If you send a SIGTERM to udhcpd directly after a SIGUSR1, udhcpd will
+finish writing the leases file and wait for the aftermentioned script
+to be executed and finish before quiting, so you do not need to sleep
+between sending signals. When the file is written, a script can be
+optionally called to commit the file to flash. Lease times are stored
+in the file by time remaining in lease (for systems without clock
+that works when there is no power), or by the absolute time that it
+expires in seconds from epoch. In the remainig format, expired leases
+are stored as zero. The file is of the format:
+
+16 byte MAC
+4 byte ip address
+u32 expire time
+16 byte MAC
+4 byte ip address
+u32 expire time
+.
+etc.
+
+example: hexdump udhcpd.leases
+
+0000000 1000 c95a 27d9 0000 0000 0000 0000 0000
+0000010 a8c0 150a 0d00 2d29 5000 23fc 8566 0000
+0000020 0000 0000 0000 0000 a8c0 140a 0d00 4e29
+0000030
+
+
+udhcpd.conf
+----------
+
+The format is fairly simple, there is a sample file with all the
+available options and comments describing them in samples/udhcpd.conf
+
+
+udhcp client (udhcpc)
+--------------------
+
+The udhcp client negotiates a lease with the DHCP server and notifies
+a set of scripts when a leases is obtained or lost. The command line
+options for the udhcp client are:
+
+-c, --clientid=CLIENTID         Client identifier
+-H, --hostname=HOSTNAME         Client hostname
+-h,				Alias for -H
+-f, --foreground                Do not fork after getting lease
+-b, --background                Fork to background if lease cannot be
+                                immediately negotiated.
+-i, --interface=INTERFACE       Interface to use (default: eth0)
+-n, --now                       Exit with failure if lease cannot be
+                                immediately negotiated.
+-p, --pidfile=file              Store process ID of daemon in file
+-q, --quit                      Quit after obtaining lease
+-r, --request=IP                IP address to request (default: none)
+-s, --script=file               Run file at dhcp events (default:
+                                /usr/share/udhcpc/default.script)
+-v, --version                   Display version
+
+If the requested IP address cannot be obtained, the client accepts the
+address that the server offers.
+
+When an event occurs, udhcpc calls the action script. The script by
+default is /usr/share/udhcpc/default.script but this can be changed via 
+the command line arguments. The three possible arguments to the script 
+are:
+
+	deconfig: This argument is used when udhcpc starts, and
+	when a leases is lost. The script should put the interface in an
+	up, but deconfigured state, ie: ifconfig $interface 0.0.0.0.
+	
+	bound: This argument is used when udhcpc moves from an
+	unbound, to a bound state. All of the paramaters are set in
+	enviromental variables, The script should configure the interface,
+	and set any other relavent parameters (default gateway, dns server, 
+	etc).
+	
+	renew: This argument is used when a DHCP lease is renewed. All of
+	the paramaters are set in enviromental variables. This argument is
+	used when the interface is already configured, so the IP address,
+	will not change, however, the other DHCP paramaters, such as the
+	default gateway, subnet mask, and dns server may change.
+
+	nak: This argument is used with udhcpc receives a NAK message.
+	The script with the deconfig argument will be called directly
+	afterwards, so no changes to the network interface are neccessary.
+	This hook is provided for purely informational purposes (the
+	message option may contain a reason for the NAK).
+
+The paramaters for enviromental variables are as follows:
+
+	$HOME		- The set $HOME env or "/"
+	$PATH		- the set $PATH env or "/bin:/usr/bin:/sbin:/usr/sbin"
+	$1		- What action the script should perform
+	interface	- The interface this was obtained on
+	ip		- The obtained IP
+	siaddr		- The bootp next server option
+	sname		- The bootp server name option
+	boot_file	- The bootp boot file option
+	subnet		- The assigend subnet mask
+	timezone	- Offset in seconds from UTC
+	router		- A list of routers
+	timesvr		- A list of time servers
+	namesvr		- A list of IEN 116 name servers
+	dns		- A list of DNS server
+	logsvr		- A list of MIT-LCS UDP log servers
+	cookiesvr	- A list of RFC 865 cookie servers
+	lprsvr		- A list of LPR servers
+	hostname	- The assigned hostname
+	bootsize	- The length in 512 octect blocks of the bootfile
+	domain		- The domain name of the network
+	swapsvr		- The IP address of the client's swap server
+	rootpath	- The path name of the client's root disk
+	ipttl		- The TTL to use for this network
+	mtu		- The MTU to use for this network
+	broadcast	- The broadcast address for this network
+	ntpsrv		- A list of NTP servers
+	wins		- A list of WINS servers
+	lease		- The lease time, in seconds
+	dhcptype	- DHCP message type (safely ignored)
+	serverid	- The IP of the server
+	message		- Reason for a DHCPNAK
+	tftp		- The TFTP server name
+	bootfile	- The bootfile name
+
+additional options are easily added in options.c.
+	
+udhcpc also responds to SIGUSR1 and SIGUSR2. SIGUSR1 will force a renew state,
+and SIGUSR2 will force a release of the current lease, and cause udhcpc to
+go into an inactive state (until it is killed, or receives a SIGUSR1). You do
+not need to sleep between sending signals, as signals received are processed
+sequencially in the order they are received.
+
+
+
+compile time options
+-------------------
+
+The Makefile contains three of the compile time options:
+	
+	DEBUG: If DEBUG is defined, udhcpd will output extra debugging
+	output, compile with -g, and not fork to the background when run.
+	SYSLOG: If SYSLOG is defined, udhcpd will log all its messages
+	syslog, otherwise, it will attempt to log them to stdout.
+	
+	COMBINED_BINARY: If COMBINED_BINARY is define, one binary, udhcpd,
+	is created. If called as udhcpd, the dhcp server will be started.
+	If called as udhcpc, the dhcp client will be started.
+	
+dhcpd.h contains the other two compile time options:
+	
+	LEASE_TIME: The default lease time if not specified in the config
+	file.
+	
+	DHCPD_CONFIG_FILE: The defualt config file to use.
+	
+options.c contains a set of dhcp options for the client:
+
+	name[10]: The name of the option as it will appear in scripts
+	
+	flags: The type of option, as well as if it will be requested
+	by the client (OPTION_REQ)
+
+	code: The DHCP code for this option
+
+busybox drop-in
+--------------
+udhcp is now a drop-in component for busybox (http://busybox.net).
+To update busybox to the latest revision, simply do a:
+
+cp *.[ch] README AUTHORS COPYING ChangeLog TODO \ 
+	<busybox_source>/networking/udhcp
+
+The only two files udhcp does not provide are config.in and
+Makefile.in, so these may need to be updated from time to time.