Helper script for releasing (Issue #20)
New function setNodeValue(...) to directly set a node's value
instead of incremental update (change). Also updates inner nodes
and prunes. Fixes issue #31.
Fix #39: Add approximate (discretized) point cloud insertion as fast variant.

Implemented as a flag for insertPointCloud() / new function computeDiscreteUpdate().
Version 1.6.3 release
Merge branch 'devel'