Build Script

Adds a python based build script and documentation.  The build script assumes that regions are now to be hosted in their own repos with a structure described in the readme.  Non-Core plugins have started to be migrated to their own repositories.

The https://github.com/CoastalResilienceNetwork/gulf-of-mexico-region region has been modified to support building by this build script.
Yeah, I should add a setting for git verbosity like I did for NSIS and MSBuild.  I was trying to reduce the amount of noise on the screen when this is running.  It's funny, what actually happens when you put in a bad repo name is that git prompts you for a username and password, since I'm cloning via https.