Renamed FrontendDeviceObserver to DeviceFrontendManager.
Added textViewSelectedDevice for each type of device, instead of the
device-title in the list.
Lowered the speed of touch-controls because it didn't handle well with
the SmartHub-movement.
Decreased code duplication A LOT in the Main-activity class. This is
done by expanding on the responsibility of the DeviceFrontendManager.
This handles all of the front-end stuff for a Device-type now (listView,
refresh, selectedDevice, enable/disable tabs, ...).