initial support for the mbed NXP LPC168

 * http://mbed.org/platforms/mbed-LPC1768/
 set message type for lowpan and ipv6 notifier
added a dedicated stacksize for float printfs
added IPv6 upper-layer checksum calculation
calculate RPL checksum right before sending the ICMP packet
make use of the IPv6 upper-layer checksum calculation
filled up IPv6 netmask correctly
Add package porting infomation
notify registered threads about _all_ received IP packets

(Before notifications were only sent for IP packets that were not
forwarded.)
pointer handling in lowpan notifier was wrong
remove profiler from lpc_common

The profiling functions (gcc -finstrument_function) should be better
defined within the application.
Merge pull request #350 from OlegHahm/ipv6_csum

IPv6 Upper-Layer Checksums
fix for the redbee-econotag Makefile to work again
fixes to build default project and clean properly
Merge pull request #335 from thomaseichinger/makefile

fix redbee-econotag Makefile
Merge pull request #403 from OlegHahm/remove_profiler

remove profiler from lpc_common
added vtimer_msg_receive_timeout
Merge pull request #402 from mehlis/vtimer-msg-receive-timeout

added vtimer_msg_receive_timeout
reverted 18e97f6dd5457538c7bf39c6abcf346f5a080ca5
daemonization, io socket and file redirection