Problem: The 'langnoremap' option leads to double negatives. And it does
not work for the last character of a mapping.
Solution: Add 'langremap' with the opposite value. Keep 'langnoremap' for
backwards compatibility. Make it work for the last character of a
mapping. Make the test work.
Problem: Loading defaults.vim with -C argument.
Solution: Don't load the defaults script with -C argument. Test sourcing
the defaults script. Set 'display' to "truncate".
