Adds Anime-specific searching and Fanzub support

Splits searching in the same way as a Daily search, each indexer has a
method to search specifically for anime. Fanzub support was also added,
with its own indexer and parser classes (which only respond to Anime requests).

My goal with this pull request is mainly to see if I am on the right track, point out any style errors / contribution problems (not sure what your testing policy is), and to get a discussion going about further support. For example, what do you want to do about Scene/Season names from TheXEM? I don't believe they are stored in the database, should they be? Or do you want them to just stay in memory? Also, on Trello you have a checkbox for 'Standard Renaming'. What do you mean by that? Is that just an option for doing the S01E01 naming vs absolute number naming?