Ability to add time when instructor will be in FabLab via Google Calendar mobile app

[pavelsr]

• Create web server for users authorization (related to Simple server with Webhook handler and GUI for managing main json config file #14 )
• Module which will fetch all events of all instructors together

Need to create a new mode for app. Mode will turn on by special setting in config.

Each instructor must have calendar with particular name where he/she will mark when will be in FabLab and what equipment is planning to use. Also it's needed to once give bot an offline access to Google API (server will be placed on special page)