Introduced Flat variant of the Dark Theme
Performance Fixes
Minor layout fixes
Merge branch 'master' into pr/105

* master: (24 commits)
  Fix mini player location at edge of screen, multiple screens (fixes #108)
  Use an NSURLProtocol instead of data: URIs (fixes #123)
  Tweak preferences window height
  Fix notifications on Safari 6/OS X 10.8 (fixes #92)
  Fix CSS for Safari 6 and OS X 10.8 (fixes #91)
  Fix mini player to work on OS X 10.8 (fixes #106)
  Modify dark.css, CustomWebView to use/hold inverted sprite sheet (fixes #90, #120)
  Revert event tap creation, fixes QuickLook but breaks Fireworks (fixes #117)
  Remember last size of mini player (fixes #96)
  Revert "Fix timestamp alignment in Last.fm popover"
  Fix timestamp alignment in Last.fm popover
  Update Last.fm API keys
  Add preference to automatically love/unlove a track on Last.fm based on thumbs up rating (fixes #83)
  Add preference for showing the Last.fm button
  Add ability to love/unlove song from Last.fm popover
  Append Last.fm icon instead of replacing other links
  Add Last.fm popover that shows 10 most recent tracks
  Add NSDate+TimeAgo to podfile
  Update Last.fm icon in preferences
  Fix album title color in dark style (fixes #101, thanks @Deanmv)
  ...
Update, tweak dark flat style (thanks @hoffi very much!)
Merge branch 'pr/105'

* pr/105:
  Update, tweak dark flat style (thanks @hoffi very much!)
  Minor layout fixes
  Performance Fixes
  Introduced Flat variant of the Dark Theme