Extract Graph class
Merge main.js into grex.js
Expose classes in gRex.ClassTypes object
Replace for loops with _.each
Rename gremlin.params to gremlin.script
Add Gremlin.appendScript() method
Remove Gremlin._buildGremlin() method
Fix a couple variables
Add CommandBuilder class
Extract Argument class
Remove utils.js. Merge functions into Argument class.