core/net/uip.h: Add missing #include <string.h>

Fixes implicit definition of memcmp() warnings/errors.

Signed-off-by: Joakim Gebart <joakim.gebart@eistec.se>
Changed the parameter 'char * data' of process_start to the
type process_data_t. This was an artifact when the choice was
made to use the void * type for the data parameter in processes.

Changed parameter 'void * data' of process_post_synch to
process_data_t for consistency.

Checked all the uses of process_start() in contiki and fixed casts
of the data parameter.
Added flags to enable 20-bit support from msp430-gcc 4.7.x
Fix SDCC Compile Error
Merge pull request #729 from g-oikonomou/fix-nd6-sdcc

Fix SDCC Compile Error
Merge pull request #637 from alignan/z1-add-flags-20bit-support

Added flags to enable 20-bit support from msp430-gcc 4.7.x
Update README.md

Adding new command for ftdi_sio which applies to Kernel>3.12 used by Ubuntu 14.04 LTS
Sender rank in Hop-by-Hop option has inverted bytes
Setting uip_ext_len again breaks hop-by-hop option
Insert properly Hop-by-Hop option at first hop
Improve RPL hop-by-hop option detection
Merge pull request #650 from cetic/pr-rpl-hbh-fixes

Fix for RPL Hop-by-Hop options
rl78: Change RIMEADDR_CONF_SIZE to LINKADDR_CONF_SIZE because the rimeaddr module has been renamed to linkaddr.
Merge pull request #734 from hexluthor/rl78-linkaddr

rl78: Change RIMEADDR_CONF_SIZE to LINKADDR_CONF_SIZE
Removing trailing whitespaces
Merge pull request #711 from gebart/upstream-fix-implicit-definitions

uip.h missing #include <string.h>
Adding a CONTRIBUTING file to use github feature

https://github.com/blog/1184-contributing-guidelines
Merges Z1SP into Z1 platform
Only wait for a keypress if the user is told to press a key.
Merge pull request #747 from oliverschmidt/master

Only wait for a keypress if the user is told to press a key.