[schema] restore constraint checking when running on old sqlite Old sqlite3 doesn't provide CHECK constraint names in error messages, preventing us from translating a backend integrity error into a ValidationError. This was added in 2012, but the sqlite3 version in RHEL6 is older; so if we run on old sqlite, keep checking the constraints in python rather than only in SQL. Closes #10927494

[web/autoform] fix regression introduced by #5758ba784ebd The changes from cset 5758ba784ebd "[autoform] when building inlined-form view for a relation, consider related entities intead of other views" lead to an unexpected 'add new' link on creation of an entity with inlined form for a relation of cardinality 1. To avoid this, we should consider formviews and not existing relations when the entity is being created. Closes #10860258

[tox] Generate test environments for Python 2.7 and 3.4 Test commands for each environment are written down explicitly since I could not find a way to extract the "package" name (e.g. "hooks") from the environment name (e.g. "py34-hooks"). For Python 3.4 interpreter, only environments (subpackages) that do not depend on cubes for their tests are listed since those test dependency cubes are not yet installable with Python 3.x. etwist is also not included since the Python 3 port is not complete at the moment. From local testing, py34 tests pass for the following subpackages: - dataimport - entities - ext - hooks - wsgi