_ prefix for all source folders
Remove clean task
Revert "Remove express & express-server dependencies"

This reverts commit 4f2f84c2832f1103d1ca9e3111264e7a009fe737.

Conflicts:
	Gruntfile.coffee
Copy index.html to 404.html
Correct paths
Remove watching of build (root) folder
Fix output path of index -> 404
Placeholder for useminPrepare
Specify <base href>
Fix 404 in templates:dest