improved Kinetis UART implementation

Add interrupt driven and queue variant implementation.
add test for extended queue functionality

add new test queueEx
add projects for MK70F - CoIDE and IAR
add original thread metric from ThreadX

Add original Thread-Metric Benchmark Suite source code from Express Logic,
Inc. to repository. At this moment, source code is without any
modifications.
add thread metric port for Kinetis MK70F

- add 8 projects for IAR (tm_benchX_twrk70f120)
- port for MK70F only