[#523] adapt cluster count when point is removed
[#523] Merge branch 'develop' into feature/523

Conflicts:
	GAE/src/com/gallatinsystems/gis/map/MapUtils.java
[#523] Code cleanup

* Use `putObject` and `containsKey` from MemcacheUtils
* This functions handle runtime exceptions, and possible null value for
  cache object
Merge pull request #533 from akvo/feature/523

[#523] adapt cluster count when point is removed