Conversion for CakePHP 2.0 and usage with composer

Address issue #2
Updating to handle CakePHP 2.0 models
Fix references to plugin. Not all plugins are loaded immediately

Note: Image_GraphViz is horribly broken in more recent versions of PHP
Going to swap for something else

Use phpDocumentor/GraphViz, since Image_GraphViz is not longer maintained

Apply CakePHP Code Standards

Change readme to md
Merge pull request #3 from rhelms/issue-2

Conversion for CakePHP 2.0 and usage with composer
Merge pull request #4 from mamchenkov/CakePHP-2.0

Cake php 2.0