Non-interactive AWS install by running a single script.

Merge branch 'master' into non-interactive-aws-install

Conflicts:
	doc/installation.md

Fix merge mess in installation.md

db/migrate/20120729131232_add_extern_auth_provider_to_users.rb

@@ -0,0 +1,8 @@
+class AddExternAuthProviderToUsers < ActiveRecord::Migration
+  def change
+    add_column :users, :extern_uid, :string
+    add_column :users, :provider, :string
+
+    add_index :users, [:extern_uid, :provider], :unique => true
+  end
+end