* Small pop-up window at the bottom of the main winodw instead
of traditional status bar, that consumes lots of space.
* API, similar to standard Qt's status bar.
* The status bar hides itself after specified amount of time.
* Clicking on the status bar also hides it.
* Properly behavies on resizes/moves/focus/etc.
* Tested on Linux and Windows.
* Replaced the search via dictionary name by search via dictionary id, cleanup
* Renamed "Dictionaries Pane" --> "Results Navigation Pane"
* Added to CREDITS
* TODO note about code duplication
It is a separate detacheable pane, which could also be enabled/disabled,
it tracks the current tab's contains, and lists those dictionaries that
contributed their content to the current translation.
Clicking on dictionary name jumps to the appropriate article from
this dictionary, which improves the navigation flow.
The Dictionaries Pane:
* Shows both dictionaries' names and icons.
* Does not consume resources when hidden.
* Properly styled.
* Properly handles app-wide shortcuts
(Esc, Ctrl-L, Alt-D, Enter, Alt-Up/Down).
