tigefa4u projects Trac

Trac can now use both psycopg and pyPgSQL postgresql drivers.

Fixed typo in trac-post-commit-hook.

Small refactoring for !WikiProcessor: removing useless `env` parameter

Fixed exception thrown when no docutils package is available

TracCrossReferences branch: Wiki Formatter refactoring

The Wiki Formatter now optionally takes into account
the source object and the facet which corresponds to
the wiki text being formatted. So do the macros.

The issues #1802 and #1829 can therefore be properly fixed:
the source object is known and does not have to be guessed
from the path info.

As a bonus, macros like the PageOutline can now work for all Trac objects.

Some refactorings on the TracCrossReferences branch:
* Attachment API simplified
* now uses a `TracObject` parent instead of `parent_type` and `parent_id` pairs
* function `attachment_to_hdf` is now the `Attachment.to_hdf` method
* unit tests changed accordingly
* Wiki and Ticket attachment code changed accordingly
* !TracObject refactorings:
* `XRef.XRefSystem` is now `TracObject.TracObjectSystem`
* `TracObject.factory` class method added
* inlined doc updates
* `WikiSystem._wiki_factory` and `TicketSystem._ticket_factory` methods added

Make sure _convert_row works as expected for all values.

pysqlite2 does not like multiple queries in a single .execute() call.

If both pysqlite1 and pysqlite2 are installed, only use pysqlite2. Probably closes #1831.

TracCrossReferences: merged with InterTrac (diff:branches/cboos-dev/intertrac-branch#1957:2022)