ADD: added multitasking lock and irq disable routine

Signed-off-by: Giuseppe Monteleone <info@ing-monteleone.com>
CHG: changed scheduling policy now we reschedule when need

Signed-off-by: Giuseppe Monteleone <info@ing-monteleone.com>
ADD: added event with flags

Signed-off-by: Giuseppe Monteleone <info@ing-monteleone.com>
FIX: protect scheduling during high level iRQ

Signed-off-by: Giuseppe Monteleone <info@ing-monteleone.com>
CHG: YOS_DbgPutc is a weak alias of YOS_T32Putc

- YasminOS user can redefine YOS_DbgPutc theirs module and this take precedence,
  redirecting debug output

Signed-off-by: Giuseppe Monteleone <info@ing-monteleone.com>
ADD: added assert function

Signed-off-by: Giuseppe Monteleone <info@ing-monteleone.com>
CHG: added functions name to YOS_KERNEL sections

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