ATS2-0.1.8

## ats2-postiats-0.1.8:

    This is the 17th release of ATS2, the successor of the ATS
    programming language. The compiler for ATS2 is given the name
    ATS/Positats, ATS2/Postiats or simply Postiats.

    The official website for ATS is:

    http://www.ats-lang.org

    ATS-Postiats is hosted at github:

    https://github.com/githwxi/ATS-Postiats

    Major releases of ATS2 are available at:

    https://sourceforge.net/projects/ats2-lang/

    Major releases of external packages for ATS2 are available at:

    https://sourceforge.net/projects/ats2-lang-contrib/

    Here is a list of major additions and changes since the last release:

    1. GCATS (GC for ATS1) is no longer used by default to build patsopt.
       Some common command-lines for building patsopt are listed below:
       ./configure && make # using no GC
       ./configure && make GCFLAG=-D_ATS_GCBDW # using Boehm-GC
       ./configure && make GCFLAG=-D_ATS_GCATS # using GCATS (GC for ATS1)