Add a PHP file that finds images instead of the AJAX call

New Features

	- Version has been risen to 0.2.0
	- AJAX call gave a 403 error when live. Fixed issue by adding a PHP file
	  that the user puts in their images directory which the AJAX call
	  now references. It returns JSON for the AJAX call to work with.
	- Added the ability for the user to declare multiple types of file
	  extensions in the Sallery.init method.
	- Updated the README.md accordingly with the new features and version.
	- Added new headers to the JS and PHP files since they sit in a directory
	  independent of the Sass directory.