Convert UI to JavaFX 2+

[UrsKR]

Over the next few months, we want to convert Anathema's UI to JavaFX 2+ and get rid of Swing.

This will fix #332 (since the menu bar in a pure application works flawlessly), #254 (since there are no system-specific L&Fs in FX) and #20 (since those proprietary calls are specific to Swing).

In addition, once we can upgrade to JavaFX 8+ with Retina Support, #310 will be fixed.

Finally, this offers a chance to fix #226 by re-implementing the editor.

We keep track of various details on the "Swing => FX" board.