Statically apply FML/Forge coremod transformers where possible

In MCPC+'s build process, access transformations are applied statically
at compile-time, via SpecialSourceMP (and source edits).

This commit removes the unnecessary duplicate runtime transformations,
since they were already applied at compile-time. Includes
ForgeAccessTransformer, MarkerTransformer, FML AccessTransformer - but
we still need to keep FML's AccessTransformer in for ModLoader
compatibility via ensurePublicAccessFor() on the mod base classes.

Minor optimization, negligible performance impact, mainly for general cleanup.