Mux is now pair friendly; Add some vim macros

* `gem install mux -v 0.6.0.pre.3` for compatible mux
* Vim macro to align gemfile versions (1 by 1)
* Vim macro to open Github issue for current line (assuming line 2 has
  Github issues URL and first word of line is issue id)
* Ditching chat pane (editor is now pane one) (still need to fix leader in vim)