pulls in the latest libdnf.

Colin Walters (15):
      postprocess: Also pick up user.pax.flags
      compose: Print stats at end of commit
      compose: Print progress during ostree commit
      Update for libhif -> libdnf
      Port to new ostree_repo_checkout_at()
      Fix accidental double __ in previous commit
      gitmodules: Update for rename
      build: Import attributes.m4 copy from systemd, update warnings
      libglnx porting: Switch to glnx_file_get_contents_utf8_at()
      compose: Port bits of postprocessing to fd-relative
      compose: Add --cache-only
      scripts: Error out if we encounter lua
      Update to latest libdnf
      core: Fix an error-handling logic error in relabel path
      Release 2016.6

Jonathan Lebon (1):
      compose: add "mutate-os-release" treefile key

Git-EVTag-v0-SHA512: 9fdd6b374f85a8d2fcda34dade8226a333b5d0ffadea88e792918e9fcf25bc887b41900c0968f34351f7a7b0a81165eabc1d0595d3937f5a77c7074650b6dfe2