Refactor Ruby singleton testing

I'm going to write a binary replacement for this that works well with
vim-vroom and running "nearest" tests to a given line number. But for
now, Rob's functions will work fine in the new name `rbtest`. Our binary
will be called `rtest` (eventually).
Allow Tmux to use the OS X clipboard.
Use vimux and vim-ruby-refactoring

Allows us to run tests in a tmux window while keeping Vim open.
Highlight search matches in shell vim.
Turn off word-wrapping in HTML and Haml documents.
Disable Vim BG clearing and use Vroom with tmux.
Use xterm-256color terminal emulation for Tmux
Refactor how we handle CTags

- Create `ct` alias for generating project-wide tag files that also
  include dependencies
- Don't generate CTags after Git pulls anymore, use the `ct` alias after
  `gur` for that functionality.
- Keep that functionality in our `bundle install` alias, but use the
  `ct` alias to maintain a common means of calling the CTags executable