Add a support note to assist users of the 2.9.x client
and point to it from any affected instructional page.
There are other command replacements that should be
done eventually (e.g. upgrade-series to upgrade-machine).
This PR only covers the incompatible commands.
Change-Id: I67f1fbfe9b0e7e568649a96c5e75499ebd86f404
Signed-off-by: Peter Matulis <peter.matulis@canonical.com>
fad1657f63