Android annotations: implement Circle, Line, Fill

[fynngodau]

Android annotations API proposal implementation PR as a part of #1491. Closes #1635.

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• Circle, Line and Fill classes are now usable.
• Updates should propagate correctly.
• Bitmaps may not work correctly if used with an annotation that is directly added to a manager. Per Android Annotations: add new classes (1) #1493 (comment), better bitmap handling and cleanup magic is in scope of Android Annotations: automatic grouping #1494.
• Existing tests for CircleManager, LineManager and FillManager have been updated, and pass.
• The following activities in the test app are modified to allow manual testing:
  • Add Markers in Bulk
  • Polygon
  • Polyline
• There is no existing activity for testing Circles; in the future, the demo activities should definitely be reworked. For now, it is easy enough to modify "Add Markers in Bulk" to use circles instead of markers for manual testing.
• To avoid conflicts, the following classes still have temporary names that differ from their intended names:
  • Annotation → KAnnotation
  • AnnotationContainer → KAnnotationContainer
• Symbol no longer has the temporary name KSymbol.
• Commented-out classes temporarily added in Android annotations: implement new Symbol class #1637 are removed or no longer commented out. The exception is DraggableAnnotationControllerTest, which will be re-added in Android Annotations: add click and drag listeners #1634.
• Unresolved TODOs are in the scope of future issues.
• For some more detailed changes, please refer to the commit log.

[louwers]

@artakka can likely have a look at the end of the week.

@fynngodau let me know if you want to merge it earlier. I left two small comments. Overall looks good to me. 👍