Add middle graphics layer

[makermelissa]

When I created this, I wanted to leave the low level matrix class as an initializer and left most of the graphics heavy lifting in the matrixportal class. Now that it has been used in several classes, I'm realizing it would be nice to have a middle layer with graphics functions such as displaying a background that would be similar to the way the network class is the middle layer on network related stuff. I think this could be done without breaking any compatibility.