On Windows, don't rsync the `apps` folder

Make `apps` a true shared folder, and have the rsync ignore it.

Otherwise, when you do "makemigrations" the migration files are created on your VM. You have to copy them out manually before your next rsync or they will be clobbered.
Merge pull request #218 from RickMohr/limit-rsync

On Windows, don't rsync the `apps` folder