Zombies burn in caves. Lighting broken.

As you can see in the pictures posted below, the lighting inside caves appears to be completely broken. This affects most of my current map. Block and sky light levels are always at 15 in all areas that apper lit underground. This causes zombies/skeletons to even burn underground. Placing/removing blocks does not trigger a light update, it just makes it even worse by increasing the light level of even more blocks. I started this map in snapshot 18w16a. When I downloaded the newest snapshots (I am currently using snapshot 18w21a) the lighting got really messed up. It would be great if you could add an option to recalculate the lighting.