2.0 upgrade

This is the PR for 2.0 release, with a substantial changelog:

- Hermes now relies on **Tmux 1.8**, mostly for its ability to pipe on copy: this removes the need for the custom launchd service and simplifies the approach used in the configuration. Other niceties have been added as well, like fullscreen panes toggle and vertical block selection.

- **Pathogen** removed in favour of **Vundle**: this makes the whole plugin management for Vim easier.

- Removes [Powerline](https://github.com/Lokaltog/vim-powerline) (deprecated anyway) for a custom, extremely lightweight status line based on <https://github.com/maciakl/vim-neatstatus>

- Hermes ships a set of default Rails projections to use with [Rails.vim](https://github.com/tpope/vim-rails)

- Autocompletion plugins have been removed in favour of a lighter, more focused custom function.

- [RVM](https://rvm.io/) removed in favour of [rbenv](https://github.com/sstephenson/rbenv). This may be controversial, but having set up at least 7-8 different laptops in the last few months, rbenv has proven to be easier and more reliable.

- Dynamic path setup: this means that Hermes can be installed anywhere in the system.

- Molokai color scheme

- Spellcheck configuration (borrowed from <https://github.com/thoughtbot>) for good documentation/commit messages editing.

- Better selection of Vim plugins, with more focus on speed and performance.

- Simple Homebrew management thanks to `brew bundle`.