EssentialGG
Build: Set `FMLModType` depending on which ModLauncher version is used
This attribute was previously set to LIBRARY before 0696479 where it was removed for the following reason:
however since we require shading and relocation on ML9 anyway, we may as well just remove it outright.
This is fine for production, but relocation does not apply in development environments. The type should be declared as GAMELIBRARY on >=ML9, and LIBRARY on <=ML8.
Anything which uses UniversalCraft should also be on the GAME layer, and cannot be on any other layer (e.g. PLUGIN) as it will not be able to access UniversalCraft classes. This includes our other libraries (UniversalCraft, Elementa). If we want those to also be usable in development environments, we'll have to ship separate artifacts of those for >=ML9 and <=ML8 with the FMLModType attribute set accordingly 😢.
This PR might be a change that needs some more discussion, and we might want to hold off on it until we decide what to do with our other libraries (although, it probably makes sense to do either way).
Related to: #70, #73.
