Started ext-clones
clones: node.clonesFind() returns list of nodes (not keys)
getNodesByRef()
Neue Funktion node.isClone(). Fixed refKey map für nocht-clones
Fixed clone list length
Merged latest changes from master
[ext-clones] new extension that introduces `refKey`, which may occur     multiple times in one tree
[ext-clones] highlight original node if a clone is created
Merge branch 'master' into clones

Conflicts:
        CHANGELOG.md
	demo/sample-ext-persist.html
	src/jquery.fancytree.persist.js
	test/test-ext-table.html
[ext-clones] New option highlightActiveClones
Merge remote-tracking branch 'origin/master' into clones
Added FNV-1a and MurmurHash3
merged from master
added defaultKey callback and reproducible unique keys
changelog
Merge branch 'master' into clones
grunt dev runs test at start
table does not need css fix anymore
isClone() retruns boolean
minor fixes in core tests