shell: Change serial_test_task to shell_task and move to shell.c.
shell: Use fio_printf instead of write.
shell: Add arrow key detection.
shell: Add history function.
shell: Combine arrow key and history function.
shell: Add history_next and combine to down arrow.
shell: Add history command to shell_task.
Update .gitignore. Ignore core file.
test: Add unit test.
Update .gitignore. Ignore test/*.txt.
Fix: typo in test-strlen.in.
Fix: Unit-test hang in reset_handler.
Fix: Missing unit-test.
host: Add SYS_CLOCK function.
Merge branch 'master' into profiling

Conflicts:
	src/kernel.c