Fix warning in CypherException
Remove extraneous println's
Fix type check for length("string") in cypher
Add size(['a', 'collection']) funtion to Cypher
Use correct type for possibleStartPoints in VarLengthRels
Make PathType a fully-fledged type
Disallow the use of a Path as a Collection
Remove Nullable
Propagate nulls through math funcs in cypher
Remove unused LabelType
Add additional type checks
Merge pull request #1357 from cleishm/size_length

Fix Cypher length("string"), add size(['a', 'collection']) and disallow use of Path as a Collection