Flightradar-client

* Added Python 3.10 support.
* Removed Python 3.6 support.
* Bumped library versions: black, flake8, isort.
* General code improvements.
* Migrated to github actions.

* Set aiohttp to a release 3.7.4 or later (thanks fabaff).
* Add license tag.
* Added Python 3.9 support.
* General code improvements.

* Added basic statistics to feed aggregator.
* Exclude tests from package.
* Added Python 3.8 support.
* Drop Python 3.5 support.

* Fixed async code and session handling
* Project and library naming streamlined

* Simple Feed Manager for all feeds added.

* Support for aiohttp library.
* Full URL configurable (instead of just hostname and port number).
* Improved error handling for aggregators.