Named providers

- YouplayProviders now have a 'name' method that return a humanized provider name
- Providers have to implement this!
Smarter Search for Stats

- Stats now depends on the contents of the search field to display statistics for certain collections
- search inside Stats just like in Log: favorites, provider:, channel:, category:, and others
- the providers line chart now includes a dataset for all videos in the collection
- providers are now spelled correctly
- the search field placeholder adapts, typeahead for Stats is disabled (for now)