* fix preferences' filepickers
* fix start_hidden again, and make it more accurate
* display popup menu window items for all applications (not only browsers)
* rework handling of attention calls for chat conversations:
  * blinking on new messages for twitter accounts
  * implement blinking (gtk_status_icon_set_blinking() deprecated)
  * support X11 urgency hint
* add support for Zotero
* add locale sk-SK (thx Slavko slavino.sk)
* minor fixes (e.g. keep long living references to timers)