Add mobidata-bw extensions

[hbruch]

This PR adds a couple of additions which where developed for mobidata-bw to stadtnavi next branch.

These changes include:

• Splitting sprite files into individual svgs and compiling them back to a sprite file during build
• addition of a mobidata-bw configuration
• split sharing map layer into differenty layers per formFactor
• in preferences, select different sharing options by formFactor and operator instead of individual feeds
• support wmst layers
• addition of aachen configuration
• further smaller improvements