* numpy version for py310

requested in #2315

* Update requirements.txt

* Fix typo in function definiton

* Swap hasattr out

hasattr(self, "speaker_manager")  and hasattr(self, "language_manager") seems to be redundant since BaseTTS defines both.

* added basic Mary-TTS API endpoints to server

- imported `parse_qs` from `urllib.parse` to parse HTTP POST parameters
- imported `render_template_string` from `flask` to return text as endpoint result
- added new routes:
  - `/locales` - returns list of locales (currently locale of active model)
  - `/voices` - returns list of voices (currently locale and name of active model)
  - `/process` - accepts synth. request (GET and POST) with parameter `INPUT_TEXT` (other parameters ignored since we have only one active model)

* better log messages for Mary-TTS API

- smaller tweaks to log output

* use f-string in log print to please linter

* updated server.py to match 'make style' result

* add energy by default

* added energy to base tts

* fix energy dataset

* fix styles

* fix test

* Update docs index

* Add MarryTTS docs

* Update docs index

* Add Overflow docs