+ Added xTaskAbortDelay() function, which causes a task to exit the Blocked state even before the timeout has expired or the event the task is waiting for has occurred.
+ For efficiency and code size reasons on some architectures, replace many instances of "== pdTRUE" with "!= pdFALSE".
+ Support tickless idle when configUSE_PREEMPTION is 0 (previously tickless idle was only supported when the pre-emptive scheduler was being used).
+ If a stack was statically allocated, then don't try freeing it if the TCB cannot be allocated.
+ Remove use of INCLUDE_xEventGroupsSetBitsFromISR() pre-processor macro, as it was not tested anyway.
Demo app changes:
+ Updated SAM4L Atmel Studio project to use Atmel Studio 7.
