Rework workflow functional testing so isn't tested by default...
Meant to be used with a specific workflow, but nose is picking it up by default when no workflow has been specified.
More work on eliminating references to test_db_util.sa_session.
... tweaked styling of several functional tests (the non-toolbox,datamanager,workflow,api functional tests) along the way - mostly PEP-8 fixes and eliminating * imports. Did not modify tests which do not pass - but did not in the source where they fail inside a TODO.