Oranchelo Team

I'm starting to think that we don't actually need `SFML_RELATIVE_INSTALL_LIBDIR` anymore when `SFML_PKGCONFIG_INSTALL_PREFIX` is replaced with `SFML_PKGCONFIG_INSTALL_DIR`. The old issue was about appending `CMAKE_INSTALL_FULL_LIBDIR` to `CMAKE_INSTALL_PREFIX` failing when `SFML_PKGCONFIG_INSTALL_DIR` was...

I think I understand enough about the pkg-config issues in the meantime, but I'm waiting until there is a consensus on https://github.com/SFML/CSFML/pull/374 to keep the SFML implementation the same as...

> SFML sets the precedent that CSFML follows so this PR does not need to concern itself too much with being consistent with CSFML. The same changes are needed in...

The code shouldn't blindly be based on what SFML is using, because that implementation is also partially broken (https://github.com/SFML/SFML/pull/2917). ~~I would expect that `${exec_prefix}/@CSFML_PKGCONFIG_INSTALL_DIR@` would be the correct path when...

I can confirm that this PR solves the issue of `libdir` being wrong when an absolute path is set in CMAKE_INSTALL_LIBDIR. However I'm not certain if it is the best...