- Fix an issue with an import that changed in the last cleanup effort (as a side note, the plugins manager test is a good one to use to check for import regressions).
- Clean up some test comments.
Not sure if this should be an interface test or a scenario test, but it does very little mocking, tries to let the bits of OpenLP run for real, and checks that all the plugins are imported.
Remove the superfluous argument to the find_plugins method.
