FakeVim: Escape '>' character in mappings

On some keyboards, '>' character can be produced using Shift key. But
recorded macro shouldn't contain '<S->>', which cannot be properly
parsed, instead it will be '<S-<GT>>' (as '<LT>' for '<').

Change-Id: Iac3759029b6ff8c9e690c4728e35048c0b6046f9
Reviewed-by: hjk <hjk121@nokiamail.com>