Settings: initial interface + color picker

- added slims clock and date customizations for status bar
- added our own modded marginov color picker which we use as default
- added initial interface settings. A bit empty currently but we are on
  alpha and it will be filled fast for sure. Added as well two empty classes
  due that we need them later
- added Proguard flags to compile the interface separately

Conflicts:

	proguard.flags
	res/xml/settings_headers.xml