main: call g_set_application_name()

I'm not sure about the advantages of calling g_set_application_name(),
because I don't use a task manager (except for ps and kill), but it
sure doesn't hurt.

src/main.c

@@ -283,6 +283,8 @@ int main(int argc, char *argv[])
 	setlocale(LC_CTYPE,"");
 #endif
 
+	g_set_application_name("Music Player Daemon");
+
 	/* enable GLib's thread safety code */
 	g_thread_init(NULL);