title: Cannot install ruby 1.9.3 using RVM. Seems to be some type of git error
body: <p>When I execute <code>rvm install ruby-1.9.3-head</code> I get this error:</p>
  
  <pre><code>➜  ~  rvm install ruby-1.9.3-head
  Installing Ruby from source to: /Users/max/.rvm/rubies/ruby-1.9.3-head, this may take a while depending on your cpu(s)...
  fatal: Not a git repository (or any of the parent directories): .git
  fatal: Not a git repository (or any of the parent directories): .git
  fatal: Not a git repository (or any of the parent directories): .git
  fatal: Not a git repository (or any of the parent directories): .git
  fatal: Not a git repository (or any of the parent directories): .git
  Branch origin/ruby_1_9_3 not found.
  There has been an error while checking out branch ruby_1_9_3.  
  Halting the installation.
  There has been an error fetching the ruby interpreter. Halting the installation.
  
  ruby-1.9.3-head is not installed.
  To install do: 'rvm install ruby-1.9.3-head'
  </code></pre>
  
  <p>Does anyone know how to fix this?</p>