- test that in scenario where user is not allowed to see original document, he is still able to convert document to different format

Add test level Document_checkConversionFormatPermission which disallow access
to original document format, and remove it conditionally in beforeTearDown.

Add helper method _test_document_conversion_to_base_format_no_original_format_access.
It asserts that document is not available in original format and then checks
if it is possible to convert this document.

Test for PDF, Open Office Document, Text and Image to cover all known cases.


git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@35957 20353a03-c40f-0410-a6d1-a30d3c3de9de