Factor out some layers to separate libraries

[makermelissa]

As suggested by @tannewt, this will make maintaining PyPortal, MatrixPortal, MagTag, and Blinka_PyPortal libraries easier to maintain.

Notable ones include the FakeRequests, WiFi Module, and possibly Graphics libraries. With this layered approach, we can even do something similar to the PyPortal library.

[makermelissa]

Ok, I'm kinda designing this as I go along. I've already split out the main MagTag functionality into the PortalBase library and
and just extending function with device specific stuff which feels like a great approach. I've also determined that I want a NetworkBase and GraphicsBase so I can guarantee certain things are available and further factor out common pieces of code. I'm passing in graphics and network objects so they can be initialized and extended with things that are specific to the board.