Refactoring Desktop UI

o Moves settings into separate dialog [INCOMPLETE]
o Move buttons to lower section of window
o Replace memory slider with ability to edit .vmoptions file
o Remove "gear.png"
o Lots of smaller visual changes (spacing etc.)
Break MainWindow into smaller classes.

o Introduce DesktopModel.
o Pull SettingsDialog into its own file.
Enable SystemOutDebugWindow by default.
Extract functionality from MainWindow into smaller classes.
Make SettingsDialog use new Components factory methods
Clean up layout of server extensions pane in settings dialog in Neo4j Desktop
Merge branch '2.0-fancy-desktop'

Conflicts:
	packaging/neo4j-desktop/src/main/java/org/neo4j/desktop/ui/MainWindow.java
	packaging/neo4j-desktop/src/main/java/org/neo4j/desktop/ui/UIHelper.java