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- Bug fix: tokens were stored in a manner that prevented them from
being cleaned up properly in the utility's _principal_ids mapping.
Make zope.locking.tokens.Token orderable to fix this, as tokens
are stored as keys in BTrees.
- Add a zope.app.generations Schema Manager to clean up any lingering
tokens due to this bug. Token utilities not accessible through the
component registry can be cleaned up manually with
zope.locking.generations.fix_token_utility.
- TokenUtility's register method will now add the token to the utility's
database connection if the token provides IPersistent.
- Clean up the tests and docs and move some common code to testing.py.
- Fix some missing imports.
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