ATS2-0.1.6

## ats2-postiats-0.1.6:

    This is the 15th 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. Reorganizing ATSLIB/prelude
    2. Improving ATS2-contrib/zeromq
    3. Adding src/Makefile_CBOOTmin for minimally C-bootstrapping ATS2:
       There is no GCATS by default
       There is no dependency on libgmp
    4. Code for level-2 jsonization is moved into
       pats_synent2_jsonize.sats
       pats_synent2_jsonize.dats
    5. Adding various functions for traversing level-2 syntax See:
       pats_staexp2_appenv.hats
       pats_dynexp2_appenv.hats
       pats_constraint3_appenv.hats
    6. Using a more compact format for representing exported constraints
    7. Using a more compact format for representing JSONized level-2 syntax
    8. Overhauling the build process for ATS1
    9. Supporting NGC-bootstrapping (via ats-lang-anairiats-0.2.11-fin)
    10. Automated testing (via Travis-CI) is substantially extended.
    11. Building ATS2 on MACOSX (via ATS1-ngc) is formally documented
    12. Adding support for bit vectors: libats/bitvec
    13. Fixing bug-2015-01-03 (see doc/BUGS), which caused an error in
        compiling certain singular flat records.
    14: Generally improving some error-handling code.