Adding veil

 - Adds ```includeVeil``` option during loading

 - Includes veil css

 Please let me know of any suggestions, as this PR is the first I've done for any project other than my own.

Questions:

 - Would we want to add something like a ```customDiv``` to allow any custom div to be added?

 - I'm not fully set up in Karma testing. Is there some material you might want to point me to to get set up and make sure all tests pass?