Since 664059fb (transport-helper: update remote helper namespace,
2013-04-17), a 'push' operation on a remote helper updates the
private ref by default. This is often a good thing, but it can also
be desirable to disable this update to force the next 'pull' to
re-import the pushed revisions.

Allow remote-helpers to disable the automatic update by introducing a new
capability.

Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Finishing touches to fc/transport-helper-error-reporting topic.

* js/transport-helper-error-reporting-fix:
  git-remote-testgit: build it to run under $SHELL_PATH
  git-remote-testgit: further remove some bashisms
  git-remote-testgit: avoid process substitution

Just like all the other shell scripts, replace the shebang line to
make sure it runs under the shell the user specified.

As this no longer depends on bashisms, t5801 does not have to say
bash must be available somewhere on the system.

Signed-off-by: Junio C Hamano <gitster@pobox.com>