Cura vs. Simplified3D

[medskm]

These slicers output different GCode, but it looks like we'll be switching to Simplified3D (perhaps staying with Cura for the Duplicator 6?).

I propose a GCodeAnalyzer to use any GCodeObject, but that the GCodeObject be an interface or superclass for CuraGCodeObject and S3DGCodeObject, or something along those lines. I've assigned this task to myself, but I think it may be a good idea to start collecting a list of issues to make consistent progress on this project.