Implement tickless
Implement tickless verification
Change tickless verify range, from event create to event trigger
enable ktimer tickless by default
kernel: conditional build of tickless scheduling
Modify tickless verification display
Fix tickless does not recover heart beat
Fix call tickless_verify_stop before start
mk: migrate to Kconfig for tickless
conditional build of tickless scheduling status tracker
Move platform dependent codes from tickless_verify to hwtimer

Signed-off-by: Jim Huang <jserv@0xlab.org>
kernel: fix build failure because of tickless
Merge branch 'test-tickless'

Fixes #19
add southernbear in author list
Save lr in each context switch.
Only compare the last 4bits in lr because
EXC_RETURN[4] in normal context is different
from one in floating point context
Support floating point context switch.
Test FPU by compiing uart baud rate and
round area in ping thread.
Merge branch 'floating_point' of https://github.com/georgekang/f9-kernel into floating_point