Break up vimrc into files for specific purposes.

Add some logic to work with a local, non-version controlled rc file whose only
job is to configure where the local git repo is and source in those separate
files without killing the current working directory from which vim was launched,
in case there is a project specific .vimrc as well.

gvimrc

@@ -0,0 +1,4 @@
+set guifont=Monaco:h14
+set lines=60
+set columns=200
+colorscheme desert