Merge pull request #5 from gogojesse/scheduler_dev

Add description of features.
Merge pull request #6 from gogojesse/scheduler_dev

Add more description for scheduler.
Merge pull request #7 from gogojesse/scheduler_dev

Add description for taskxx.
Merge pull request #9 from gogojesse/scheduler_dev

This is a git pull-request command line test.
Merge pull request #10 from gogojesse/scheduler_dev

Scheduler dev
Merge pull request #11 from gogojesse/scheduler_dev

remove gos_main.o from gos.lds to fix gdb source level issue.
Clean scheduler test/debug code.

Signed-off-by: gogojesse <gogojesseco@gmail.com>
Fix timer interrupt clear issue.

Signed-off-by: gogojesse <gogojesseco@gmail.com>