On the multiple_ssl_impls branch: Merge trunk up to r2024.
Revs 2022 and 2023 were already merged manually, so this revision only records
the merged revisions.


git-svn-id: https://svn.apache.org/repos/asf/serf/branches/multiple_ssl_impls@1699562 13f79535-47bb-0310-9956-ffa450edef68