Search for subgames using $MINETEST_SUBGAME_PATH.
Translated using Weblate (Japanese)
Add Indonesian Language
Fix broken plantlike drawtype.
Fix syntax error in Japanese translation
Remove remenants of mob code

Since minetest has no mobs within the core anymore, I suppose these
settings and code should go. Any mod that uses `minetest.setting_getbool`
will work with no problem since the default return value is `false`.
Remove m_ext_ptr in GUIFormSpecMenu, replaced by refcount mechanism