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.

Servers/ProtocolServer/PSClientConnection.cpp

@@ -7,7 +7,7 @@
 static HashMap<int, RefPtr<PSClientConnection>> s_connections;
 
 PSClientConnection::PSClientConnection(CLocalSocket& socket, int client_id)
-    : ConnectionNG(*this, socket, client_id)
+    : IClientConnection(*this, socket, client_id)
 {
     s_connections.set(client_id, *this);
 }

Servers/ProtocolServer/PSClientConnection.h

@@ -7,7 +7,7 @@
 class Download;
 class SharedBuffer;
 
-class PSClientConnection final : public IPC::Server::ConnectionNG<ProtocolServerEndpoint>
+class PSClientConnection final : public IClientConnection<ProtocolServerEndpoint>
     , public ProtocolServerEndpoint {
     C_OBJECT(PSClientConnection)
 public:

Servers/ProtocolServer/main.cpp

@@ -19,7 +19,7 @@ int main(int, char**)
         }
         static int s_next_client_id = 0;
         int client_id = ++s_next_client_id;
-        IPC::Server::new_connection_ng_for_client<PSClientConnection>(*client_socket, client_id);
+        new_client_connection<PSClientConnection>(*client_socket, client_id);
     };
     return event_loop.exec();
 }