qml: setup key lut and modifier constants
qml: hookup keyboard, fixes #200

* Special modifier handling for darwin required. See
  http://qt-project.org/doc/qt-5.1/qtcore/qt.html#KeyboardModifier-enum.
Merge branch 'qml_hookup_keyboard' of https://github.com/EdVanDance/lime into EdVanDance-qml_hookup_keyboard

Conflicts:
	frontend/qml/main.go
frontend/qml: update changed lines

Some odd things going on, but at least it's better than it was before