[fitswcs] WCSLIB 7.3 released

[Mark Calabretta]

Greetings,

WCSLIB 7.3 is now available:

   ftp://ftp.atnf.csiro.au/pub/software/wcslib/wcslib.tar.bz2

It contains a number of minor fixes and enhancements, as per the change
log appended below.

Mark Calabretta



WCSLIB version 7.3 (2020/06/03)
-------------------------------

* C library

  - wcshdo() was writing MJD-OBS twice to the header, and MJD-BEG not
    at all.

  - In wcshdo(), if MJDREF assumes its default value, just write
    MJDREF = 0 (not MJDREFI & MJDREFF), and omit writing DATEREF,
    which, with a value of '1858-11-17', looks strange and is
    potentially confusing.  Reported by Thomas Robitaille.

    If the fractional part of MJDREF is zero, then just write the
    integer part as MJDREF (i.e. not as MJDREFI & MJDREFF).

  - Bug fix in wcsfix() - it was writing error messages that referred
    to DATE-REF and MJD-REF rather then DATEREF and MJDREF.  Reported
    by Mihai Cara.

  - Under control of a new flag, WCSHDR_DATEREF, added the option to
    wcspih() and wcsbth() to accept DATE-REF, MJD-REF, MJD-REFI,
    MJD-REFF, JDREF, JD-REFI, and JD-REFF as synonyms for the standard
    keywords, DATEREF, MJDREF, MJDREFI, MJDREFF, JDREF, JDREFI, and
    JDREFF.  The latter buck the pattern set by the other date keywords
    ({DATE,MJD}-{OBS,BEG,AVG,END}), thereby increasing the potential
    for confusion and error.

* Fortran wrappers

  - As compilers are becoming much stricter (gfortran 10), modified all
    Fortran test programs to use the type-specific equivalents of the
    various *PUT and *GET routines.  Reported by Ole Streicher.

  - For the fitshdr wrappers, added type-specific equivalents of
    KEYGET: KEYGTI, KEYGTD, and KEYGTC.

* PGSBOX

  - Modified pgtest to use the type-specific equivalents of WCSPUT.

* User manual

  - In the section "WCSLIB Fortran wrappers", promoted use of the type-
    specific equivalents of the various *PUT and *GET routines.

  - In the section "FITS-WCS and related software", added ASCL and ADS
    codes, where they exist, for all software packages mentioned.

  - Documentation generation moved to doxygen 1.8.18 (was 1.8.17).