Actually add the generator. gitignore is weird.

.gitignore

@@ -1,7 +1,7 @@
 *swp
 *gem
 .sass-cache/
-bourbon/
+/bourbon/
 demo/
 tmp/
 tags

lib/bourbon/generator.rb

@@ -0,0 +1,81 @@
+require "fileutils"
+
+module Bourbon
+  class Generator
+    def initialize(arguments)
+      @subcommand = arguments.first
+    end
+
+    def run
+      if @subcommand == "generate"
+        generate
+      elsif @subcommand == "update"
+        update
+      end
+    end
+
+    def update
+      if bourbon_files_already_exist?
+        remove_bourbon_directory
+        generate_files
+        puts "Bourbon files updated."
+      else
+        puts "No existing bourbon installation. Doing nothing."
+      end
+    end
+
+    def generate
+      if bourbon_files_already_exist?
+        puts "Bourbon files already generated, doing nothing."
+      else
+        generate_files
+        puts "Bourbon files generated to bourbon/"
+      end
+    end
+
+    private
+
+    def bourbon_files_already_exist?
+      Dir.exist?("bourbon")
+    end
+
+    def generate_files
+      make_lib_directory
+      copy_in_sass_extensions
+      copy_in_scss_files
+    end
+
+    def remove_bourbon_directory
+      FileUtils.rm_rf("bourbon")
+    end
+
+    def make_lib_directory
+      FileUtils.mkdir_p("bourbon/lib")
+    end
+
+    def copy_in_sass_extensions
+      FileUtils.cp(File.join(lib_directory, "sass_extensions.rb"), "bourbon/lib/")
+      FileUtils.cp_r(File.join(lib_directory, "sass_extensions"), "bourbon/lib/")
+    end
+
+    def copy_in_scss_files
+      FileUtils.cp_r(all_stylesheets, "bourbon/")
+    end
+
+    def all_stylesheets
+      Dir["#{stylesheets_directory}/*"]
+    end
+
+    def stylesheets_directory
+      File.join(top_level_directory, "app", "assets", "stylesheets")
+    end
+
+    def lib_directory
+      File.join(top_level_directory, "lib", "bourbon")
+    end
+
+    def top_level_directory
+      File.dirname(File.dirname(File.dirname(__FILE__)))
+    end
+  end
+end