dd510b0286
- Rename _package_alternative_inner() to _find_package_alternative() and modify it to make it more useful when called from other functions. If a package is found that matches one of the alternatives, its name is printed on stdout, otherwise nothing is printed (empty output). - Adapt _package_alternative() accordingly and rename it to _mandatory_pkg_alternative(). - New function _optional_pkg_alternative() based on _find_package_alternative(). Contrary to _mandatory_pkg_alternative(), if no match is found in _optional_pkg_alternative(), a message is printed to stdout but the script doesn't abort.