Problem: Various inconsistencies in test files.
Solution: Add modelines where they were missing. Use Check commands instead
of silently skipping over tests. Adjust indents and comments.
(Ken Takata, closes#6695)
Problem: Some balloon tests don't run when they can.
Solution: Split GUI balloon tests off into a separate file. (Ozaki Kiichi,
closes#4538) Change the feature check into a command for
consistency.
Problem: 'langmap' applies to the first character typed in Select mode.
(David Watson)
Solution: Check for SELECTMODE. (Christian Brabandt, closes#572)
Add the 'x' flag to feedkeys().
