Pyscript 0.30 release

The 0.30 release contains a number of new features, and several bug fixes.

The main new features are:

• support for apps and importable modules and packages below the <config>/pyscript directory
• support for trigger functions as closures, allowing factory functions to create multiple similar trigger functions
• added a variable pyscript.config that allows access to yaml configuration settings
• added task.executor() for functions that block (eg, doing I/O) or have long running times
• added support for with, async for, lambda and named expressions
• use the croniter package for cron functions
• improved exception handling and reporting

Breaking changes:

• task.unique() now only applies within the current global context; the same name used in other global contexts will not be affected
• accessing an undefined state variable now throws a NameError exception, instead of returning None, except in @state_trigger or @state_active, where undefined state variables, attributes or the .old value will still evaluate to None if not defined

Infrastructure:

• moved documentation from README to hacs-pyscript.readthedocs.io and added more material
• added precommit checks for black, isort, flake8 and pytest
• set line-length to 109 for black/flake8/isort
• revamped pytest setup
• improved test coverage

Bug fixes include:

• variable scoping in function closures now works correctly
• fixed augmented assignments
• list/set/dict comprehension looping vars are now in implicitly nested scope
• del works correctly for non-locally scoped variables
• sunrise and sunset times now correct for dates other than today

Thanks to @fleXible for several PRs (adding croniter, fixing sunset/sunrise, revamping test infrastructure, refactoring and precommits, among others) and @dlashua for extensive testing, various bug reports and feature requests.

Enjoy!