Initial commit
Add mongodb-10gen formula

* Reference: http://docs.mongodb.org/manual/tutorial/install-mongodb-on-ubuntu/
Update folder structure to fit salt-formula
Add 'formula/mongodb-10gen/' from commit '35c19c8fe105c83a6c75f23576f32253333c90cf'

git-subtree-dir: formula/mongodb-10gen
git-subtree-mainline: 0494db9279b34afdd87c7d4114edd5de3e663b0b
git-subtree-split: 35c19c8fe105c83a6c75f23576f32253333c90cf