Beta release with fixes for a few outstanding issues, including adding line items using a method borrowed from uc_taxes, which will hopefully fix the tax and shipping bugs that have been reported.
This release includes mainly just bug fixes.
If upgrading from version 5.x-2.1 or earlier, please read release notes for 5.x-2.2-rc2.
This is the last release candidate before a stable release, if no serious bugs will be found, it will be marked as a stable release in a week.