Function start 

pub fn start(timer: impl TimerSource, int0: SoftwareInterrupt<'static, 0>)

Starts the scheduler.

The current context will be converted into the main task, and will be pinned to the first core.

This function is equivalent to start_with_idle_hook, with the default idle hook. The default idle hook will wait for an interrupt.

For information about the arguments, see start_with_idle_hook.