An SML/NJ smackage. (Sort of.)

This package isn't *really* a package of SML/NJ. SML/NJ has a wacky
subversion repo layout that I didn't really want to deal with
mirroring in git.

This package is a simple script to fetch and build SML/NJ and a simple
script to install symlinks to the sml/nj binaries in a useful place.

This is then packaged up as a smackage to make it easy to get an
sml/nj install.

SML/NJ doesn't version according to the semantic versioning spec, so
the version number for the smackage is really a version number for the
installer script.