Modules: drop State/coptercontrol as it is unused
pios_queue: add
all targets: add pios_queue.c to makefile
all flight: use pios_queue
all flight: use PIOS_free() instead of vPortFree()
all flight: use PIOS_malloc() instead of pvPortMalloc()
System/systemmod: use PIOS_heap_get_free_size()
all targets: use PIOS_heap_initialize_blocks()
osx pios_heap: add stub for PIOS_heap_initialize_blocks()
posix pios_heap: add stub for PIOS_heap_initialize_blocks()
PiOS mutex, queue, semaphore, thread: hide implementation using uintptr_t
all pios_sys: remove redundant irq disable in PIOS_SYS_Reset()
all targets main: add headers for vTaskStartScheduler()
pios.h: remove FreeRTOS headers and tick macros
all PiOS: harmonize usage of portEND_SWITCHING_ISR()
pios_mutex, pios_queue, pios_semaphore, pios_thread: add doxygen function descriptions
Merge pull request #1289 from lilvinz/pios_queue

Pios queue