renamed sockaddr to sockaddr_t in socket_hal.h to avoid clashes with other socket libs (e.g. boost). Removed global sockaddr in spark_utilities - was only used from one place.
Merge branch 'feature/hal' of https://github.com/spark/core-firmware into feature/hal
wip xcompile HAL, basic wlan and TCP sockets.
Merge branch 'feature/hal' of https://github.com/spark/core-firmware into feature/hal