Remove autotool builds

[andriish]

Remove autotool builds.
The reasons:

• autotools are not good in general:
  • not a very portable with poor support of even common compilers
  • very bloated -- see the volume of deleted "code" even in this pull request
  • for any non-trivial changes one has to do run the autoreconf
  • for releases one has to run autoreconf and include the results in the tarball
• all the functionality is duplicated in the cmake
• the deletion ensures the cmake builds will be used -- means there will be APFELConfig.cmake installed and the integration of apfel with other cmake projects will be as simple as

find_package(APFEL)
.....
target_link_libraries(mytarget PRIVATE APFEL::APFEL APFEL::APFELEvol)

• the deletion makes possible to make the releases on github in couple clicks -- no need to regenerate the configure scripts.

However that is up to you to decide and makes sense only if you are familiar with cmake at least a bit.

[scarrazza]

Thanks @andriish, I am totally in favour of dropping autotools.

[alecandido]

I also agree: you're also properly testing CMake, and only the tested workflow should be left (the duplication is not useful).

[alecandido]

@andriish just be aware that there are people packaging APFEL, e.g.

https://github.com/NixOS/nixpkgs/blob/nixos-23.05/pkgs/development/libraries/physics/apfel/default.nix#L22

and they might rely on autotools.

Luckily, they are also clever enough to use a fixed tag (and I believe just a few people are using those packages).

[andriish]

Hi @scarrazza , concerning the nixos --I'm sure they will be happy to use CMake. Just because if there are small problems in autotools one has to patch *a lot * of stuff, while for CMake it is just one file.

[alecandido]

I agree, autotools requires a lot more effort to be maintained, and it is less and less used as a build system.

I was just raising the issue of downstream (another example is myself, but of course I can also fix it by myself).