Added the initial structure for a Symfony Validation handler that is injected into the parsers.
Built parse-merging into the ApiDocExtractor.

Wired up a "post-parse" pass to allow recursive parsing across multiple parsers.
Fixed multi-level validation nesting.

Removed "class" parameters from results after processed.

Updated README.
Updated postParse logic to utilize an interface and to avoid unnecessary "supports" checks.

Expanded documentation on new classes and methods.
Merge pull request #210 from jhallbachner/validation2

Added Support for Validation Component (refactored)