style fixes
Preloading of nanosec data
New layer in between NETSTACK_MAC and NETSTACK_NETWORK:
NETSTACK_LLSEC
Doing hdrreduce in NETSTACK_LLSEC, so that the NETSTACK_LLSEC driver can
see the entire frame.
Configuration option for defining a constant LoWPAN-wide IEEE
802.15.4 security level
CC2420: Doing CRC in hardware all the time
CC2420: Macros as functions for saving program memory