WIP
Merge remote-tracking branch 'origin/master' into ThinningNode
- (finally) Added functional thinning node/op
- 4 Thinning algorithms: Hilditch, Zhan Sue, Guo Hall and morphological
ToDo: further cleanup/documentation /Icon.
- Documented and drawn.
- More polish
- Small change to exception message.
Merge branch 'ThinningNode'

Conflicts:
	org.knime.knip.base/src/org/knime/knip/base/nodes/proc/ProcNodeSetFactory.java