Fix nova coverage.

Nova coverage was broken because additional coverage tests were added
that interfere with collecting coverage during unit testing. These new
tests were not properly excluded by the coverage unit test regex. Modify
the regex to exclude any tests of the form '.*test.*coverage.*'. This
allows `tox -ecover` and `run_tests.sh --coverage` to run properly.

Change-Id: Id35f50ec335707c9eadb0e7fb3aa0833661f7333
Make compare_result show the difference in lists

If two lists had differed because one had an extra element, both lists
would be included in the exception message. If the lists were large (for
example the list of extensions) it could be very difficult trying to
figure out what is different between the two lists.

This change will show the items that only exist in the expected and/or
result and not the other list.

Change-Id: I6102faea037b4f5e31361adc9db81e79592b7008
Merge "Make compare_result show the difference in lists"
Merge "Fix nova coverage."