Parsing the specification has become its own class.

Templating has been abstracted, now beautifying is built into all php
generation.  We lose the singleton efficiency, it gained us a few seconds
at most.

Generation tasks are split into ITasks, and are fed the main CG object
as if it were a configuration object.  Eventually we will want to make
the configuration a first-class object so that it is customizable.

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* CRM-13871: Provide an ORM layer: Doctrine
  http://issues.civicrm.org/jira/browse/CRM-13871