Allow preemptive/tocks mode to be disabled

Add support for terminating background threads

Use the null scheduler while invoking tock hooks to prevent infinite recursion

Fix CI config

Use named argument for readability

Add support for TockHooks

Stabilise initialisation/uninitialisation

Update dependencies

Ensure that we always switch context at least once per program/request

Update dependencies

Expose shout API

Update dependencies

Be consistent

Tidy

Update dependencies