LibIPC: Rename base classes to IClientConnection and IServerConnection

This matches what we're already calling the server-side subclasses
better, though we'll probably want to find some better names for the
client-side classes eventually.

Libraries/LibProtocol/Client.cpp

@@ -5,7 +5,7 @@
 namespace LibProtocol {
 
 Client::Client()
-    : ConnectionNG(*this, "/tmp/portal/protocol")
+    : IServerConnection(*this, "/tmp/portal/protocol")
 {
     handshake();
 }