Major Update to dotfiles

## What's up??
This is a major update to me dotfiles, most notably, I've switched over to using fish shell and am now use `rake` to handle the bootstrapping/installation of all dotfiles.

## TODO
- [ ] Move all of my aliases in `fish/config.fish` to separate functions in separate files.
- [ ] Add a `rubocop.yml.symlink` file to hold all of my `rubocop` settings.
- [ ] Colorize the terminal output when installing and symlinking files.
- [ ] Skip the step for setting fish as the default shell if fish is already the default shell.
- [ ] Prompt the user for info about setting up their `gitconfig`. Refer to https://github.com/holman/dotfiles & https://github.com/ryanb/dotfiles for inspiration.
- [ ] Investigate whether I actually need to use `oh-my-fish` or if I can: (1) install it as a submodule (2) get by with just rolling all of the needed plugins and themes as my own.
- [ ] Update `README` to offer a clear explanation of how and why to use the dotfiles.
- [ ] Update all of my os x defaults to be more complete. Refer to https://github.com/mathiasbynens/dotfiles for ideas.
- [ ] Better handle a user being on a non OSX machine.
- [ ] Install and set up rbenv
  - [ ] Install rbenv via homebrew
  - [ ] Install rbenv plugins
  - [ ] rehash rbenv
- [ ] Add a `editorconfig.symlink` file to my editors directory to hold my editor settings.
- [ ] Add `pry.symlink` to `ruby` directory in order to have my pry themes always installed.
- [ ] See if I can remove the `fish/fishd` file and just use the one that are installed with fish.
- [ ] Investigate what other worthwhile bin files I can add to my dotfiles. Check out https://github.com/pengwynn/dotfiles/tree/master/bin