Collective-indexing

---------------------------------

* Don't activate event subscriber support by default as it can have
performance implications.
[witsch]

* Make the wrapper used for unindexing return the correct acquisition parent.
This fixes http://plone.org/products/collective.indexing/issues/6 as well
as http://dev.plone.org/plone/ticket/10088
[witsch]

---------------------------------

* Improve logging of auto-flushes for easier performance tuning.
[witsch]

* Add support for Zope 2.12.
[wichert]

* Made all but one test work on both Plone 3 and 4 by relying on fewer internal
details of the functions under test.
[hannosch]

* Adjusted tests to set a site explicitly in the layer.
[hannosch]

* Changed zope.app.event imports to zope.lifecycleevent. The former was
deprecated since Zope 2.10.
[hannosch]

* Fix event subscriber for `IObjectModified` events without a description.
[gweis]

-----------------------------

* Patch `CatalogTool.getCounter` to process the indexing queue before
returning the counter indicating catalog changes (aka auto-flush).
[witsch]

----------------------------

* Register import and export steps using ZCML.
[witsch]

----------------------------------

* Add support for GenericSetup.
[witsch]

* Add configlet to allow TTW activation and configuration.
[witsch]

* Update code to (almost) comply to PEP8 style guide lines.
[witsch]

* Added logging to monkey patches.
[swampmonkey]

------------------------------------

* Provide a workaround for an issue with indexing objects using stale
acquisition chains after moving them in an event subscriber.
[witsch]

* Optimize "auto flushing" to prevent unnecessary component lookups.
[witsch]