v2.0.0 Major OAuth/ESP8266 Update

v2.0.0 is a major update with the project refactored to separate concerns into their own modules.

• Added: OAuth authentication support
• Added: ESP8266 board compilation support
• Added: Over-The-Air (OTA) firmware update support
• Added: New feature to automatically close door after set time
• Added: New API command /device to get device info
• Added: MIT license and credits
• Improved: Complete refactor
• Improved: Debug and logging
• Improved: HTTP request processing
• Improved: WiFi connection logic (no longer blocks processing)