2MGFX and MGCB Docs

Added sections for 2MGFX and MGCB docs modified from the existing Wiki entries.  Once these are published on the website we will delete the wiki entries and send people to the website instead.

This was also an experiment in a workflow for editing docs.  After creating and pushing a branch up to my fork I completely worked from the GitHub interface to create new MD files and edit existing ones.  I could also edit the config.xml to link in the new MD files.