Adds a new script to simplify deleting old files from a directory.

Created in response to a tmp/sessions/ directory filling up with tens of thousands of session files on a staging server.
Corrects docs-generate to be compatible with phpdoc v2.6.
Updates usage text to properly escape arg descriptions.
Updates phpdoc required version to 2.x stable.
Updated readme and cleaned up old TODO markers.
Merge pull request #26 from loadsys/f/delete-old-files

F/delete old files