Rename GIT_FOO to GIT_FREEBSD_FOO to avoid confusion
Script to do checkouts and make a sandbox.
Cleanup: Remove traces of SVN/CVS and patches.
Refactor git checkouts.

Make use of the cache for initial checkout, but then switch
to using the real repo "github" to avoid confusion.

Consolodate src and ports into one function.
Fix the check for root before build.