Import ruby200-awesome_nested_set-2.1.6 as databases/ruby-awesome_nested_set.

An awesome nested set implementation for Active Record.
Added databases/ruby-awesome_nested_set version 2.1.6
+ruby-awesome_nested_set
Import ruby200-xpath-2.0.0 as textproc/ruby-xpath.

XPath is a Ruby DSL for generating XPath expressions.
Added textproc/ruby-xpath version 2.0.0
+ruby-xpath
The qmail-bigdns patch currently redirects to https. Put a copy on
MASTER_SITE_LOCAL.