Refactor storage layer to allow for new repository filesystems using drivers. (Reviewed by Cynthia Shang.)
Refactor IO layer to allow for new compression formats, checksum types, and other capabilities using filters. (Reviewed by Cynthia Shang.)
* Refactor Ini.pm to facilitate testing.
* Complete statement/branch coverage for Ini.pm.
* Improved functions used to test/munge manifest and info files.
* Fixed an issue where read-only operations that used local worker processes (i.e. restore) were creating write locks that could interfere with parallel archive-push. (Reported by Jens Wilke.)
* Simplify locking scheme. Now, only the master process will hold write locks (archive-push, backup) and not all the local and remote worker processes as before.
The stanza-upgrade command provides a mechanism for upgrading a stanza after upgrading to a new major version of PostgreSQL.
Contributed by Cynthia Shang.
