Chapter on Hashtables in ATS2TUTORIAL

See:

http://ats-lang.sourceforge.net/DOCUMENT/ATS2TUTORIAL/HTML/HTMLTOC/book1.html

For many programmers, using ATSLIB can be a frustrating/intimidating
experience. ATSLIB is
actually meant for people to quickly build their own library packages. In
this new chapter, I showed
a way to do so (myhashtblref.hats).

Cheers!