Merge pull request #101 from msavazzi/master

Fixed scraper restart / cross thread crash
fixed: loading defaults in MediaSources
fixed: text on API key buttons
fixed: some MovieSet issues
added: change tv show language to context menu
added: missing language strings
merge: latest state
fixed: missing language
fixed: more missing language
added: new movie set panels
fixed: TMDB API key issue
fixed: image dialog movie(-set)  title
added/renamed: MovieSetScrapeOptions / ScrapeOptions to MovieScrapeOptions
added: new MovieSet options
renamed: PosterScrapers to MoviePosterScrapers
test: MoveSet panel
fixed: panel name
merge: latest state
merge: latest state
code: cleanup