Add USING PERIODIC COMMIT to Prettifier

o Untangle Prettifier parser along the way
Convert PrettifierTest to CypherFunSuite
Merge pull request #2070 from boggle/2.1-pc-prettifier

2.1 Prettifier support for USING PERIODIC COMMIT
Merge pull request #2071 from davidegrohmann/2.1-loadcsv-docs-and-field-terminator-fix

Load CSV reference docs
File url can open path containing special chars (e.g., &?%)
* Clean up and simplification of the code
Adding cookie manager for downloading csv from websites which requires the client to handles cookies