Basic implementation of LPM-related functions for MSP430 MCUs
Sets MCU frequency in 'board.h', instead of the common 'cpu.h' file
Added the LPM_UNKNOWN constant to the enum 'lpm_mode'
for respresenting unknown/unavailable LPM-related status.
function 'lpm_get()' now returns LPM_UNKNOWN by default
ipv6_sendto: return the success
Merge pull request #459 from rousselk/msp430-lpm-freq

Msp430 lpm freq
Merge pull request #504 from mehlis/ipv6-send-return-value

ipv6_sendto: return the success
removed getting started text from doxygen mainpage
removed pointer to RIOT repository from README
remove duplicate LICENSE in boards directory
removed getting started documents as it has been merged into the wiki
added information from Introduction page to the API start page
Merge pull request #502 from OlegHahm/boards_documentation_update

Boards documentation update
Auto init destiny
Start POSIX net [pnet] module
Implement file descriptor table

Needed for pnet
Implementation of close()
Define stdin, stdout and stderr
Wrap RIOT socket API
Add auxilary headers