Update Documentation for Version 2

[Rican7]

Issue edits ongoing.....

(reference: https://github.com/Rican7/klein.php/tree/klein-v2)

OOP Changes

• Change simple respond examples to add:
  • An autoload require_once
  • A Klein app instanciator
  • A $app-> reference for the Klein method calls
• Change "with" example
  • To use ( $app )
  • To have the included files reference $this with the respond calls

API Changes

Breaking

Added functionality

• $response->onError has a new, optional "allow_duplicates" argument
• New OPTIONS request support (make sure to document the OPTIONS route too)
• New HEAD request support (automatic, like a GET without the "body")

Sections to Add

• Unit testing (how and why)
• Contributing (how, best practices, code standards, PHPDocs, etc)