Added .idea to gitignore
Make discount a real submodule
Migrated discount and adjusted config to be XCode only
Merge branch 'master' of github.com:toland/qlmarkdown into feature-discount-submodule

Conflicts:
	discount
Imrpoved discount updater

Changed discount updater to automatically checkout the submodule if
necessary. The old `update-discount.sh` file is no longer necessary,
so perhaps we'll remove it soon, but it's been left for posterity.