Merge changes from NOIRLABs version

[olebole]

This PR contains (most of) the changes made in https://github.com/noirlab-iraf/fitsutil

Not applied:

• cfitsio updates (we use the cfitsio library provided by IRAF),
• mkfloat.sh usage (we use mkfloat; it is better that the tool name does not reflect the used shell type)
• Replacing realloc() calls with calloc() in https://github.com/noirlab-iraf/fitsutil/commit/008b762a3bbd38db5a073e9536952792da2480ba (see #8)
• Adding and removing binaries
• Re-(ab)using macosx as architecture name for Mac/ARM: First, there is no advantage to re-use the name for a different architecture, and then, the name is wrong now: the current OS for Macs is called macOS and no longer Mac OS X. macos64 was introduced in IRAF 2.17 and will be kept now.

Current status is https://github.com/noirlab-iraf/fitsutil/commit/ecc4f912e8b8326ce18f03368d219ad01c3f5542

Cc @mjfitzpatrick who authored the changes.