Changes submodules to track master branches (I think)

Hi Russ,

Looks like git 1.8.2 added the ability to track branches on submodules.  I think I've configured this to do so, but it's a little unclear to me, so only accept the pull request if it works (or at least doesn't break anything) for you.

See these two pages for more info:

http://stackoverflow.com/questions/9189575/git-submodule-tracking-latest/9189815#9189815


http://stackoverflow.com/questions/1777854/git-submodules-specify-a-branch-tag/18799234#18799234


- Andy