LibIPC+LibGfx: Templatize IPC encoding as well as decoding

Now most classes dictate how they are serialized and deserialized when
transmitted across LibIPC sockets. This also makes the IPC compiler
a bit simpler. :^)

Libraries/LibIPC/Decoder.cpp

@@ -136,4 +136,13 @@ bool Decoder::decode(Dictionary& dictionary)
     return true;
 }
 
+void dongle() {
+    ByteBuffer buffer;
+    BufferStream stream(buffer);
+    Decoder d(stream);
+    Vector<String> x;
+    d.decode(x);
+}
+
+
 }