Add mapping to swap " for '
Add mapping to swap " for '

This is something that `surround.vim` could do for me in minor cases,
but in some larger situations, like swapping out a lot in old JavaScript
or in old Puppet configs, I don't want to find each one individually, I
just want to grab a section and swap all at once. Now ";s" in visual
mode does just that, easy-peasy.

sycobuny/rcfiles,sycobuny/rcfiles