* Clean docstrings as they has moved to IDocumennt interface

* Conversion Cache Documents are not stored anymore on Document itself.
  Use Cache Plugin to handle Storage of conversion.
  Flare is used by default as a persistent storage


git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@27932 20353a03-c40f-0410-a6d1-a30d3c3de9de