* add partial application syntax and some tests
* remove unnecessary error message and hasPartial function from parseNewArguments
* add types for PartialExpression
* Update the tests
* rename PartialExpression to Partial
* move Partial from expressions to types and rename to ArgumentPlaceholder
* add tests for ArgumentPlaceholder in babel-generator
* rename Partial to ArgumentPlaceholder
* update the tests
* remove alias from the type and undo changes in generated folder
* adds a nice error message
* better definition for the type
* auto-generated files
* update the conditional for allowPlaceholder message and tests
* update CallExpression definition to accept ArgumentPlaceholder
* change description
* clean up
* indent ArgumentPlaceholder entry and revert unwanted changes
