Issue description:

When trying to input biofuel into the biogen(or e.g. coal to heat gen) it seems
that all sides except the left side work.

Here is a screenshot of the setup:

After changing the getSlotsForFace() method in TileEntityBioGenerator.java it works fine, but I am not sure if that has any side effects:

    @Nonnull
    @Override
    public int[] getSlotsForFace(@Nonnull EnumFacing side) {
        return new int[]{0};
    }

Steps to reproduce:

1. Place down a biogen
2. Connect a transporter to it on right side
3. Try to extract biofuel from chest

Version (make sure you are on the latest version before reporting):

Forge: 14.23.5.2825
Mekanism: Latest 1.12 commit on github

Recent Mekanism builds for 1.15 have all sides but the right side accessible for the fuel slot in the Heat Generator and Bio Generator.

Seems like the block rotation may also be inverted when you place them, the other side works fine though.
For some reason the side that should output the energy even accepts the biofuel

The functionality seems intended - that side only allows access to the Charge Slot. Remember that Mekanism is strongly sided in most cases

The functionality seems intended - that side only allows access to the Charge Slot. Remember that Mekanism is strongly sided in most cases

I wasn't aware of the charge slot and I agree that this seems intended.
Maybe making the sides configurable would be a nice feature in the future since I never used the charge
slot of the generators.
In the meantime maybe making it more obvious which side belongs to which slot would be nice.