Sort indexes according to ILimitedResultIndex support. Indexes without the support are queried first, so the indexes supporting the feature already get a limited result set.

Make the tests a bit faster, there's really no difference between 100 and 1000 catalog entries. Testing really large numbers would be a different and interesting story.

Removed catalog length migration code. Direct upgrades from Zope 2.7 and earlier are no longer supported.

Don't produce warnings in our tests, only catch warnings for the one method that actually is supposed to emit it