Add -ddump-core-from-renamer and -ddump-core-final

c.f. -ddump-stg-from-core and -ddump-stg-final.

I think that -ddump-core-final is what -ddump-simpl outputs, but I'm not 100% sure. It's documentation says

Dump simplifier output (Core-to-Core passes)

which doesn't sound right at all. At least it's not what it does, with optimizations one there are multiple simplifier passes, and -ddump-simpl seems to dump the final one, which is actually an output of TidyCore pass (which is a last pass in default pipeline?).