Improve use as child project, HDF5 build, and CI

• correct bugs in HDF5 build
• improved use as child project
• modernized CI for latest runners

autobuild HDF5, netcdf if needed. CMake >= 3.19

CMake >= 3.19 required to facilitate HDF5,ZLIB, Netcdf auto-build if needed

numerous lessons-learned packaging improvements.

add read/write slice option, add %create(..., fill_value=) method

add %create(..., fill_value=) method with optional fill_value

add %deflate() method to check deflate_level of dataset

add option to slice (istart, iend, stride) on dataset read/write

correct read char segfault, add fpm, enhance find

• correct read character segfault discovered with GCC 12 on Linux and Windows.
• add fpm (Fortran Package Manager)
• enhance FindHDF5 and FindNetCDF

remove autobuild

v1.6.0

remove autobuild

CI shared builds, improve HDF5 and netcdf find, cleanup

v1.5.1

use tests layout

improve polymorphic

improve internal implementation of polymorphic variables, improving build time and reliability

add code coverage test, remove unused pathlib module

v1.4.7

ci:dependency

flatten install dirs, don't override cache var netcdf_external

v1.4.6

simplify link statement. Don't override cache.

use JSON urls, ci build, shared libs

• use JSON for URLs as best practice
• CI tests NetCDF build
• put Rpath in exe for shared builds