Improve FITS WCS keyword (with versions) detection

[rmathar]

The sextractor WCS keyword search in src/fitswcs.c gets
confused when a FITS header is using additional FITS
versions A-Z (like CD1_1A, CRVAL1A,...) of the FITS 4.0
standard of 2016/2018 that are not the primary FITS keywords:
https://fits.gsfc.nasa.gov/standard40/fits_standard40aa-le.pdf
[In fact these are defined already in the FITS 3.0 standard of 2010...]

It would be better if in conjunction with sky coordinates the wildcard patterns
with the fitsfind() functions would be narrower than they currently
are, i.e. if the would exclude keywords that end on the capital
letters A to Z.
[One way of implementing this would be to replace the wstrncmp()
function in fits/fitsmisc.c with something like the fnmatch() function of the
gnu libc or the regcomp()/regexec() of the POSIX standard
such that general wildcard patterns beyond the simple ? patterns
would be supported, then to tune the fitsfind() calls that way.]