The Oracle dialect sets "transactional DDL" to False by default,
as Oracle does not support transactional DDL.
fixes #245
Merge branch 'master' into multi_branch

Conflicts:
	docs/build/changelog.rst
- update tests and tweak to account for that history now includes the starting
rev in the list
- some refactoring
- call branch names "branch labels", make them unambiguously
just labels