- vim-mode V now works as expected: it starts/stops visual-line mode, regardless of whether visual mode is in effect.  Also, now always properly extends to line.
- Added preliminary code to handle :s and :%s using Leo's existing find machinery.
  This makes sense to me because : commands do not affect the dot, but might be debatable

Leo build: 20140822115819
Fixed a crasher caught by pylint.

Leo build: 20140822120104