Fix compatibility with newer releases of persistent which changed the repr of TimeStamp.
Merge branch 'perfmetrics'

Conflicts:
	CHANGES.txt
	buildout.cfg
	relstorage/adapters/schema.py
	relstorage/storage.py
	setup.py
Merge branch 'perfmetrics'

Conflicts:
	setup.py
Fixed another test that was freezing with MySQL.
Merge pull request #2 from NextThought/master

Unpack error with newer releases of persistent
Add support for the ``postgres://``, ``mysql://`` and ``oracle://`` URI schemes for zodburi.