Lots of xml comments added. Documentation updated.

Removed extension methods to be able to compile for .net framework 2.0

Lidgren.Network/NetDeliveryMethod.cs

@@ -1,6 +1,5 @@
 using System;
 using System.Collections.Generic;
-using System.Linq;
 using System.Text;
 
 namespace Lidgren.Network
@@ -13,11 +12,35 @@ namespace Lidgren.Network
 		//
 		// Actually a publicly visible subset of NetMessageType
 		//
+
+		/// <summary>
+		/// Indicates an error
+		/// </summary>
 		Unknown = 0,
+
+		/// <summary>
+		/// Unreliable, unordered delivery
+		/// </summary>
 		Unreliable = 1,
+
+		/// <summary>
+		/// Unreliable delivery, but automatically dropping late messages
+		/// </summary>
 		UnreliableSequenced = 2,
+
+		/// <summary>
+		/// Reliable delivery, but unordered
+		/// </summary>
 		ReliableUnordered = 34,
+
+		/// <summary>
+		/// Reliable delivery, except for late messages which are dropped
+		/// </summary>
 		ReliableSequenced = 35,
+
+		/// <summary>
+		/// Reliable, ordered delivery
+		/// </summary>
 		ReliableOrdered = 67,
 	}
 }