Fix a few resource leaks
Some more documentation writing
FeOSWifi: support MSG_DONTWAIT and TCP_NODELAY
Kernel: add reentrant-safe fifoGetRetValue32() function
Kernel: some minor cleanup
Kernel: add FeOS_GetSystemInfo()
Kernel: add internal API for CPU exception handling
Kernel: fix fifoGetRetValue32() (return value follows FIFO, not LIFO)
vars.mk: minor tweak
stdint.h: add (u)intptr_t