Pytimers

What's Changed

- Added `py.typed` file to mark full type checking compliance.
- Created manually triggered release pipeline to [Test PyPi](https://test.pypi.org/project/pytimers/).

What's Changed

- Implemented support for async context manage usage using contextvars.ContextVar.
- Context manager now returns clock.Clock to expose clock.Clock.duration and clock.Clock.current_duration.
- Logging moved outside of the Timer class and implemented as a separate trigger.
- Deprecating Timer.named for Timer.label.
- Sphinx documentation added.