Remove Taps gem

* Preferred method is via `pgbackups` and `pg_restore`.
* We have a `db-load-production` script in thoughtbot/dotfiles that
  wraps up the preferred method.
Improving README

* Tightened language.
* Alphabetized.
* Removed old reference to Taps gem.
Remove rarely-used items

Use zsh shebangs.
[#31] Depend on zsh publicly, and sh where possible

* This was accidentally reverted in a previous commit.
* Also fixes a typo in README.
include mountain lion version in readme related to command line tools installation
[#17] Install Homebrew using Ruby 1.9.2

Some users are reporting that they've removed /usr/bin/ruby on their
machine due to other circumstances.

So, install Ruby before Homebrew, then use the Ruby we know we have.
[#12] Use clang to install Ruby 1.9.2
Update Homebrew install line
Update RVM install line
Upgrade Ruby and Bundler

* Ruby 1.9.3 is working well for us on real apps in Heroku production.
* Bundler 1.2.0.rc2 provides a `ruby` directive that is becoming our
  standard for defining the Ruby version for the project.
Remove unnecessary Ruby version install

RVM automatically installs the stable version of Ruby so we don't need
to explicitly set a Ruby version.

The current version of RVM installs Ruby 1.9.3p194.
Update Credits and add LICENSE file

* Add MIT license file
* Add Credits section with copyright and contributors link
Install reattach-to-user-namespace

* Improves tmux compatibility with other systems.
* Better copy-paste: http://goo.gl/DN82E.
* Better RubyMotion: http://goo.gl/WDlCy.
[#32] Run each command "successfully"

* Halt execution of the script at the point that something fails.
* Update total expected time now that `brew install qt` is faster.
* Combine scripts into one file so we don't have to duplicate or
  source the `successfully` function.
Fix install for Mountain Lion and RVM 1.16

* Install Homebrew before RVM.
* Fix permissions.
* Install GCC 4.2.
* Use GCC dependencies listed by RVM.
* Use RVM version 1.15.10 because RVM 1.16.0 is broken with zsh.
* Use a one-step Ruby default.
Put RVM/Homebrew settings in ~/.zshenv

Move from ~/.zshrc in order to not conflict with thoughtbot/dotfiles.
Don't specify Bundler version

The latest, 1.2.1, works well with modern Ruby apps. No longer and need
to specify 1.2.x release candidates.
Install thin

Group gem installation into one line.
Remove deprectated Heroku gem, add CLI client

The Heroku gem has been deprecated, and Heroku recommends installing the client CLI from toolbelt.heroku.com. It's a binary, but you can install the "standalone" version (https://toolbelt.heroku.com/standalone) via wget.
Change wget to curl in Heroku CLI setup script

wget isn't pre-installed on OSX machines.