Move the boxen plugin before the homebrew plugin as homebrew's behavior depends on whether boxen is loaded
Add a ruby-version-manager plugin which intelligently decides which ruby version manager is loaded
Update ZSH completions
The rbenv completion is sourcing a file so it should not have a leading underscore in the name
Move compinit into an after_completions hook since that's the command that actually loads the completions

We need to do it there because it's not until that point that we know the fpath (where ZSH looks for completions) is stable
Move the setting of the ZSH fpath (where ZSH looks for completions) into the completion.env file

It makes more sense here since it's setting an environment variable, but also, if we do it in the zshrc file, we're actually not sure that the plugin list is stable since plugins like 'operating-system' and 'ruby-version-manager' can alter the plugins which should be loaded.
Extract the name of the Tmux socket file out into an environment variable
Add OSX functions for manipulating pairing users
Remove the tush command so that we can replace it with the new pair command
First draft of the new pair command