Reactor blocks do not properly render underwater.

[Flanks255]

• Minecraft: 1.16.5
• Forge: 36.1.32
• Powah: 2.3.16

Issue description:

Reactors do not properly render underwater.

Steps to reproduce:

Build a reactor underwater.

usually caused by the blocks internally being transparent.

[Flanks255]

If there is a specific reason the reactor blocks need to be non-solid, it can also be fixed by returning True on Block:shouldDisplayFluidOverlay