Announce: Flatpak 1.6.2 released

[Alexander Larsson]

Due to a combination of some behaviour in flatpak and recent versions
of ostree we at some point lost the use of deltas for the initial
install case, instead always falling back to a full ostree operation
which is a lot less efficient for pulls with many small files
like a runtime. This caused some very slow installs from e.g. flathub,
so I recommend everyone update to this version to get better install
performance.

Other changes are:
 * We now correctly handle TMPDIR env var overrides when bwrap is setuid
 * Disallow running "flatpak run" under sudo (as it doesn't work and
causes issues)
 * Fix build with older versions of glib
 * Minor documentation updates
 * Updated translations

Available at:
  https://github.com/flatpak/flatpak/releases/tag/1.6.2

$ sha256sum flatpak-1.6.2.tar.xz
8d27038b521bb1bcc3f42702e82ae0b11216a34db600640b9ae23f606cb9690a
flatpak-1.6.2.tar.xz