feat($urlencoded) #8 - Add form parser

A recursive descent parser for HTMLFormElements.
fix($interceptSubmit): #8 - Logic for determining type of request

If `enctype="application/x-www-form-urlencoded"` or `method="GET"`:
  urlencoded form submission
Else:
  multipart encoded form submission
docs(ajax-form.js): Add method signatures and descriptions in doc strings
chore($build): Add/configure grunt-contrib-watch task