2.8 drops `register_module`, i use `register_module`

[zeffii]

https://wiki.blender.org/index.php/Dev:2.8/Source/Python/UpdatingScripts
this states why.

I think i'll migrate the code to those conventions before 2.8 hits, but this will depend on things that are not necessarily in my control.

[zeffii]

committed here and to git.blender.org/addons