added new function create_hosted_zone_private

This adds base level support for creating private Route53 zones.

lib/fog/aws/requests/dns/create_hosted_zone.rb

@@ -50,6 +50,33 @@ module Fog
           })
         end
       end
+      
+      def create_hosted_zone_private(name, vpc, options = {})
+        optional_tags = ''
+        if options[:caller_ref]
+          optional_tags += "<CallerReference>#{options[:caller_ref]}</CallerReference>"
+        else
+          #make sure we have a unique call reference
+          caller_ref = "ref-#{rand(1000000).to_s}"
+          optional_tags += "<CallerReference>#{caller_ref}</CallerReference>"
+        end
+        if options[:comment]
+          optional_tags += "<HostedZoneConfig><Comment>#{options[:comment]}</Comment></HostedZoneConfig>"
+        end
+        if vpc[:VPCId] and vpc[:VPCRegion]
+          optional_tags += "<VPC><VPCId>#{vpc[:VPCId]}</VPCId><VPCRegion>#{vpc[:VPCRegion]}</VPCRegion></VPC>"
+        else
+          raise "Must specify VPCId and VPCRegion for private zone."
+        end
+
+        request({
+          :body    => %Q{<?xml version="1.0" encoding="UTF-8"?><CreateHostedZoneRequest xmlns="https://route53.amazonaws.com/doc/#{@version}/"><Name>#{name}</Name>#{optional_tags}</CreateHostedZoneRequest>},
+          :parser  => Fog::Parsers::DNS::AWS::CreateHostedZone.new,
+          :expects => 201,
+          :method  => 'POST',
+          :path    => "hostedzone"
+        })
+      end
 
       class Mock
         require 'time'