Re-fixed issue #25
optimizing issue #25
optimizing again #25 (a test)
Added settings for transparency in overview (issue #89)
Added the third statistics operator
fix issue #103
some corrections concerning the mode
Move the common spatiotemporal view to a new package
Updated version number; fixed a bug in statistics
Added json package in the project
Fixed issue #101: temporal axis view
Merge branch 'master' into milestone-1.1.2