fixes to listing movies

- remove thumbs.db from list
- handle missing metadata.json files
initial support for TV shows

- list TV shows (not able to see/play episodes yet)
- tweak movie list to display title from metadata (instead of folder
name)
removed old grunt
updated grunt
fix jshint for server/client side code checks
adjusted paths to run from main dir

run `node src\app.js` from root
instead of `cd src` and `node app.js`
initial cucumber tests
add example preferences file
Merge remote-tracking branch 'origin/develop'