- prereq.c (conflicts, resolve, prereq): renamed "conflicts" to
"old_conflicts"
- prereq.c (new_conflicts, resolve, prereq): also test whether any of the
conflicts of the package we're about to add matches an installed or
considered package
- test/conflict, test/instconf: test for conflicts introduced by package
about to be added
- prereq.c (installed_conflicts, free_conflicts, prereq): collect list of
pre-existing conflicts in installed packages
- prereq.c (prereq): check if package being requested already conflicts
- test/instconf: regression test for conflicts with installed packages
- TODO: updated for full support of conflicts. Mention that we're not
terribly efficient with handling conflicts.