Added homebrew formula

bash-git-prompt.rb

@@ -0,0 +1,23 @@
+require "formula"
+
+class BashGitPrompt < Formula
+  homepage "https://github.com/magicmonty/bash-git-prompt"
+  url "https://github.com/magicmonty/bash-git-prompt/archive/2.0.tar.gz"
+  head "https://github.com/magicmonty/bash-git-prompt", :using => :git
+  sha1 "3c0bc71302b97260cf8d14a1f01be732039365b9"
+
+  def install
+    prefix.install Dir['./*']
+  end
+
+  def caveats; <<-EOS.undent
+    Add the following lines to your .bashrc:
+
+    if [ -f #{prefix}/gitprompt.sh ]; then
+      . #{prefix}/gitprompt.sh
+    fi
+
+    For further information see the README.md in #{prefix}
+    EOS
+  end
+end