Allow the user to specify an arbitrary root container.

minidlna.c

@@ -690,7 +690,8 @@ init(int argc, char **argv)
 				runtime_vars.root_container = IMAGE_ID;
 				break;
 			default:
-				DPRINTF(E_ERROR, L_GENERAL, "Invalid root container! [%s]\n",
+				runtime_vars.root_container = ary_options[i].value;
+				DPRINTF(E_WARN, L_GENERAL, "Using arbitrary root container [%s]\n",
 					ary_options[i].value);
 				break;
 			}

minidlna.conf

@@ -71,6 +71,7 @@ model_number=1
 #   + "M" - "Music"
 #   + "V" - "Video"
 #   + "P" - "Pictures"
+#   + Or, you can specify the ObjectID of your desired root container (eg. 1$F for Music/Playlists)
 # if you specify "B" and client device is audio-only then "Music/Folders" will be used as root
 #root_container=.