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-rspec/desc.snippet

@@ -0,0 +1,5 @@
+require 'spec_helper'
+
+describe ${1:`Snippet_RubyClassNameFromFilename()`} do
+	${2}
+end