[Amibe] QEMDecimateHalfEdge: fix a NullPointerException
[Amibe] stitch: better exception reporting
[mesh-algos] Fix a NullPointerException
[Amibe] Replace the Triangle.vertex array by 3 attributes

Reduce the Triangle memory footprint by 16 bytes (or 40 bytes without Oops)
without changing the execution speed.
[Amibe] ImproveEdgeConnectivity: use TObjectIntHashMap.adjustOrPutValue

because it's faster than put+get.