Fix PMD warnings.
Initial PEG parser for Cypher
Rename Function traits
Add type checking

And move all functions to a common interface
Add USING SCAN hint
Support NOT Expression

Without the braces (ie. NOT(Expression))
Renable semantic checking WITH clases
Fix ordering error with converting long chains to legacy query
Handle statements with no matches or updates
Fix test
Lookup symbols in parent state
Use scoped semantic state for return items
Ensure aliased expressions are handled correctly
Add relationship index query
Add literal null
De-dup rel types
Don't make named patterns outgoing
Use LongType instead of IntegerType in most places
Add AST object for ordering