Custom leaves aren't opaque with "fast" graphics

Status
Fixed
Issue description

The issue happens both in 1.12 and 1.14 and is caused by the custom leaves overriding the getBlockLayer() method, setting it to CUTOUT.

Issue comments

I have fixed this bug, but existing custom leaves will have to be opened and saved again.

In 1.12.2, it seems it is not possible to fix this bug, I have removed CUTOUT parameter in 1.12.2 but it does not help, fancy parameter seems to not get set for custom blocks so I will leave it with fancy by default.