Refactoring BTPoint as a class to enable adoption of Annotationprotocol
Adding transit colors as constants
First attempt to replace pins with template images for station points. NOTE: tintColor on MKAnnotationView seems not to work
Merge branch 'master' of https://github.com/schluchter/berlin-transport

* 'master' of https://github.com/schluchter/berlin-transport:
  Refactoring BTPoint as a class to enable adoption of Annotationprotocol