Remove .ruby-{gemset,version} out of control

This is something each one shuold set up for himeslf. Issue came out due to on
rbenv ruby version has no `ruby-` prefix, thus before it will resolve version
by stripping prefix out it fails. And this leads into an insane `vim` boot up
time with `vim-rails` plugin.
Merge pull request #193 from ixti/remove-ruby-locks

Remove .ruby-{gemset,version} out of control