Replace DnDns with HeijdenDns

HeijdenDns seems to do a better job at querying SRV records

MinecraftClient/Protocol/Dns/Records/RecordRT.cs

@@ -0,0 +1,76 @@
+using System;
+/* http://tools.ietf.org/rfc/rfc1183.txt
+
+3.3. The Route Through RR
+
+   The Route Through RR is defined with mnemonic RT and type code 21
+   (decimal).
+
+   The RT resource record provides a route-through binding for hosts
+   that do not have their own direct wide area network addresses.  It is
+   used in much the same way as the MX RR.
+
+   RT has the following format:
+
+   <owner> <ttl> <class> RT <preference> <intermediate-host>
+
+   Both RDATA fields are required in all RT RRs.
+
+   The first field, <preference>, is a 16 bit integer, representing the
+   preference of the route.  Smaller numbers indicate more preferred
+   routes.
+
+   <intermediate-host> is the domain name of a host which will serve as
+   an intermediate in reaching the host specified by <owner>.  The DNS
+   RRs associated with <intermediate-host> are expected to include at
+   least one A, X25, or ISDN record.
+
+   The format of the RT RR is class insensitive.  RT records cause type
+   X25, ISDN, and A additional section processing for <intermediate-
+   host>.
+
+   For example,
+
+   sh.prime.com.      IN   RT   2    Relay.Prime.COM.
+                      IN   RT   10   NET.Prime.COM.
+   *.prime.com.       IN   RT   90   Relay.Prime.COM.
+
+   When a host is looking up DNS records to attempt to route a datagram,
+   it first looks for RT records for the destination host, which point
+   to hosts with address records (A, X25, ISDN) compatible with the wide
+   area networks available to the host.  If it is itself in the set of
+   RT records, it discards any RTs with preferences higher or equal to
+   its own.  If there are no (remaining) RTs, it can then use address
+   records of the destination itself.
+
+   Wild-card RTs are used exactly as are wild-card MXs.  RT's do not
+   "chain"; that is, it is not valid to use the RT RRs found for a host
+   referred to by an RT.
+
+   The concrete encoding is identical to the MX RR.
+
+
+ */
+
+namespace Heijden.DNS
+{
+	public class RecordRT : Record
+	{
+		public ushort PREFERENCE;
+		public string INTERMEDIATEHOST;
+
+		public RecordRT(RecordReader rr)
+		{
+			PREFERENCE = rr.ReadUInt16();
+			INTERMEDIATEHOST = rr.ReadDomainName();
+		}
+
+		public override string ToString()
+		{
+			return string.Format("{0} {1}",
+				PREFERENCE,
+				INTERMEDIATEHOST);
+		}
+
+	}
+}