Initial commit

Signed-off-by: Giuseppe Monteleone <info@ing-monteleone.com>
Various fix...

Signed-off-by: Giuseppe Monteleone <info@ing-monteleone.com>
Various fix. Task 1 run

- added Handler part of YOS_Start (SYS_CAL(START))
- fixed findTask. Staking is an hardware procedure so we cannot interfere. We have to save
  psp every task switch.
- YOS_AddTask fixed calculation about initial task stack. Added T bit in task xPSR
- Added space for trace (32 byte)

Signed-off-by: Giuseppe Monteleone <info@ing-monteleone.com>
FIX: System Ticks vector

Signed-off-by: Giuseppe Monteleone <info@ing-monteleone.com>
FIX: fixed ld script correct startup (.bss zero and .data copy)

Signed-off-by: Giuseppe Monteleone <info@ing-monteleone.com>
FIX: scheduler don't work

- fixed save/restore context function. Now naked function and not inline
- fixed Os start. Now there is a separate Start routine that run in handler mode and
  has control over register usage
- changed set pending logic. Now there is a macro that have to close every irq
- changed SVC routine. now parameter is svc number (1-255) svc 0 is reserved for OS start

Signed-off-by: Giuseppe Monteleone <info@ing-monteleone.com>
Add readme and licence file

Signed-off-by: Giuseppe Monteleone <info@ing-monteleone.com>