Updates the core System Classes by removing the Gateway class and binding
various APIS to a new Monal class.

Adds new APIS and updates the existing ones, and adds classes for
statically accessing each API.

Adds base Model and Respository classes.
Updates all class files to use spaces instead of tabs, inline with PSR
guidelines.
Merge branch 'master' of https://github.com/juice49/Monal into juice49-master
Fixes #4