At the moment, when attempt is built on the last one, "not yet answered"
message is shown, which confuses many people. This patch modifies the state to
"complete" for attempt based on previous and modifies the output string.

Many thanks to Tim Hunt for guiding me through quiz infrastructure and some code
suggestions.

The use case is importing of incomplete XML preset - keep current + preset changes. This also discards any pending changes.

Conflicts:
	theme/bootstrapbase/style/moodle.css

Merge branch 'm26_MDL-40200_Notices_When_Viewing_Profile_Invalid_UserId' of https://github.com/scara/moodle

This includes improved role creation, allowed roles are editable and other improvements.

Merge branch 'mdl26dev-MDL-40130-let-course-category-caching-be-used' of git://github.com/brki/moodle