Merge TUDPServer and TTCPServer into TNetwork

this gets rid of a bunch of unclear cases which I mistakenly created
while refactoring for this rewrite. One example is having to call into
TTCPServer to do UDP sending in some cases.

src/Common.cpp

@@ -21,6 +21,7 @@ void Application::GracefullyShutdown() {
         Handler();
     }
 }
+
 std::string Comp(std::string Data) {
     std::array<char, Biggest> C {};
     // obsolete