Unified permissions

Full refactoring and a redesign of the permissions database and its use throughout. Simply adding to the database will provide users access to Jeeves through text, Telegram, and via inbound phone.

What's Changed

• Activate endpoint tests, test Telegram by @preritdas in #80
• Config-configured consistent timezone by @preritdas in #83
• Run tests on chat history filterers by @preritdas in #84
• Move docs to GitBook by @preritdas in #85
• Refactor everything by @preritdas in #88
• Organize tests into subfolders by @preritdas in #89
• Unified permissions throughout by @preritdas in #91

Full Changelog: v1.5.2...v1.5.3