Make StgHugs use the same naming scheme as GHC does for class +
instance machinery.

Add machinery to do Z-encoding/decoding of names extracted from
interface files.

Make the ELF object loader work again.  It seemed to have suffered
slight bitrot over the past couple of months.  Fix various minor bugs.

Track a small change in interface file syntax.

Make Printer.c print tagged-unboxed stack sections in a decent way
now that Alastair-style stack tags have been abandoned.