Tomodachi

- Fixes an issue with live reloading on code changes (development mode) with services utilizing `protobuf` messages, which in same edge cases could trigger a repeated `TypeError("A Message class can only inherit from Message")` that would prevent the service from restarting correctly.

- Added an additional way of gracefully triggering shutdown of a running service, by using the new `tomodachi.exit()` function, which will initiate the termination processing flow in the same way as signaling `SIGINT` or `SIGTERM`. The `tomodachi.exit()` call can additionally take an optional exit code as an argument to support new ways of catching service operation.
- The process' exit code can also be altered by changing the value of `tomodachi.SERVICE_EXIT_CODE`, however using the new `tomodachi.exit` call with an integer argument will override any previous value set to `tomodachi.SERVICE_EXIT_CODE`. The default value is set to `0`.

- Handle exceptions lower in the stack for messaging services (AMQP and AWS SNS+SQS handlers), which now allows catching exceptions in middlewares, which was previously not possible. (github: **justcallmelarry**)
- Improved documentation for uses of `tomodachi.get_service` (github: **jmfederico**)
- Type hint annotation improvements.

- Adds the possibility to add a function called `_stopping_service` to the `tomodachi` Service class, which is run as soon as a termination signal is received by the service. (github: **justcallmelarry**)
- Fix for potential exceptions on botocore session client raising a `RuntimeError`, resulting in a tomodachi "Client has never been created in the first place" exception on reconnection to AWS APIs.
- Added Python 3.10 to the CI test matrix run via GitHub Actions.
- Additional updates for compatibility with typing libraries to improve support for installations on Python 3.10.
- Supports `aiohttp` 3.8.x versions.
- Supports `tzlocal` 3.x and 4.x releases.

- Pins `aiobotocore` to use up to 1.3.x releases, since the 1.4.x versions session handling currently causes issues when used.

- Now pins the `tzlocal` version to not use the 3.x releases as it would currently break services using scheduled functions (the `schedule` decorator, et al) if `tzlocal` 3.0 is installed.
- Updated classifiers to identify that the library works on Python 3.10.
- Added the new `Framework :: aiohttp` classifier.