Updated unit tests on the correct branch number this time.

Refs #7681
Tidy up system test to remove file extension.

Refs #7681
Revert "Merge branch 'feature/7861_new_mantid_widget' into develop"

This reverts commit b20a9bee0ce6c5241cc757e539fb3838e6b72c2e, reversing
changes made to 7b05c33a7aee6cb77720a55261419d5b9d7da57c.
Merge branch 'feature/7681_new_mantid_widget' into develop