Improve install

• use sha256 to check HDF5 and ZLIB source hash
• don't needlessly export--just default install to build dir for same effect and more reliable
• note that HL is not needed but implied and silently accepted

better / simpler install defaults

also enhance external project not rebuilding each time

cmake bugfix: build if template change

• Cmake build bugfix: detect template change and regenerate
• update cmake presets and use them in CI

auto-find HDF5 from installed package

install: find HDF5 automatically

packages using h5fortran install no longer need to find HDF5 themselves

install Find*.cmake

This facilitates finding HDF5 robustly, as we believe our FindHDF5 is better suited to h5fortran use cases than the CMake factory FindHDF5.cmake

CI enhancements

Use CDash as a first-class CI use case.
Eliminated intrinsic-shadow warning.

script fixes

• FindHDF5.cmake: fix detection of self-built HDF5 on Unix-like OS
• build_hdf5.py: bugfix and allow building git revision or download zip

allow HDF5 install to be outside build dir

This allows user to specify HDF5_ROOT and ZLIB_ROOT to say ~/lib_gcc so that the HDF5 library can be built and installed just once.

int64 read 0d..3d write 0d..7d

add ability to read/write int64 data. The HDF5 Fortran interface doesn't currently have an H5T_NATIVE_INT64 so we assume the int64 data on disk is H5T_STD_LE64.

If needed, we can add read int64 for 4d..7d in the future.

improve packaging, generate h5fortran.pc

• generate h5fortran.pc for pkg-config
• improve packaging
• export targets to build dir