[MLton] Basis Library and PackLargeReal{Big,Little} structures

[Vesa Karvonen]

The Basis library spec does not seem to support having structures
named PackLargeReal{Big,Little}:

  http://www.standardml.org/Basis/pack-float.html

I think that this is either an oversight or just a totally unnecessary
restriction and I'd like to make these structures visible in MLton's
"default" Basis library implementation.

Note that MLton already implements them

  http://mlton.org/cgi-bin/viewsvn.cgi/mlton/trunk/basis-library/real/pack-real.sml?rev=5892&view=auto

but they do not seem to be exported from the basis by default.

Any objections?

-Vesa Karvonen