Updated all plugins that are non-forked. Added some new plugins.

Added update_plugins.py which can fetch new plugins from GitHub.

New plugins added: zencoding, vim-indent-object, taglist, nginx.vim

sources_non_forked/snipmate-snippets/ruby-rails/defnew.snippet

@@ -0,0 +1,8 @@
+def new
+	@${1:model_class_name} = ${2:ModelClassName}.new
+
+	respond_to do |wants|
+		wants.html # new.html.erb
+		wants.xml  { render :xml => @$1 }
+	end
+end${3}