Manual typos
Improve the messaging for LOAD CSV + USING PERIODIC COMMIT failures
Fix assertions
Fix handling of null property values for nodes in CREATE, MERGE, and SET

o Create ignores
o Merge throws
o Set removes
Improve error messages for unsupported property types
Add rewriter to solve arithmetic expressions using literals
Add rewriter for naming pattern elements
Add rewriter for normalizing match predicates
Refactor tests to use CypherFunSuite instead of FlatSpec
Update the test for the invalid property value type error message
Merge pull request #2075 from boggle/2.1-null-pattern-props

Fix handling of null property values for nodes in CREATE, MERGE, and SET
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