OSTree v2015.3

[Colin Walters <walters verbum org>]

OSTree v2015.3 is now available via this GPG signed tag:

https://git.gnome.org/browse/ostree/tag/?id=v2015.3

This version of OSTree has a critical bugfix for the "bare-user" mode repositories
that I broke with v2014.2.  This repository mode is used for the PoC app
containers: http://lwn.net/Articles/630216

The static delta work is picked up again with work from Giuseppe, Alex and me.
It's still a preview, but I'm increasingly confident we can finalize the format
and ship a version 0 within a few months.

There's some internal performance optimizations, and improvements
from several people to the pull progress output.  Notable is Matthew's
commit which fixes the "percentage keeps bouncing around" problem.

Thanks to all contributors!

$ git shortlog v2015.2..v2015.3
Alexander Larsson (3):
      Fix ostree_repo_list_static_delta_names
      Allow creating and pulling static deltas starting from "empty"
      static delta generation: Separate max chunk size from min fallback size

Colin Walters (25):
      Two 32 bit compilation fixes
      Release 2015.2
      repo: Deduplicate some code in load_file
      repo: Fix bare-user file loads
      deltas: Do not traverse all objects, only both commits
      deltas: (trivial) delete some debugging prints
      checksumutils: Support splicing stream to arbitrary checksum type
      core: Add an API to parse a content file using dirfd relative lookup
      Change OstreeFetcher to be dirfd-relative
      pull: Delete processed delta parts
      deltas: Use *at() for writes
      admin: (cleanup) Add internal API to find a deployment given an index
      cmdline: (cleanup) Add internal helper to parse key=value options
      sysroot: Add ostree_sysroot_write_origin_file() API
      admin: Add set-origin command
      deltas: Unlink temporary metadata files before processing
      deltas: Drop async content writes
      deltas: Use trusted writes
      traverse: Fix transfer on hash table
      commit: Fix segfault on async writes if object exists and checksum requested
      pull: Distingiush delta pulls from loose better
      pull: Further extend static delta progress
      build: Add --disable-static-deltas
      Explicitly label .origin files as configuration
      Release 2015.3

Giuseppe Scrivano (3):
      static-delta: do not accept both --from=REV and --empty for generate
      editor: honor arguments environment variable
      static-delta: limit the number of writes in process to 1

Matthew Barnes (4):
      fetcher: Add a priority value to async requests
      pull: Prioritize fetching metadata objects over content objects
      repo: Report metadata fetch progress separately
      doc: Manpage love for static-delta command