Landing bot restrictions

[Tim Penhey]

Hi all,

I'm sure everyone is aware of the landing bot changes that have gone in
from CI.  While these are painful now, they are helping us improve our
test passing percentages.

There was a pressure release valve added, the "JFDI" flag, to override
the restrictions.

I've seen this flag used more often than it really should.  Please don't
just add it because you think your branch is "really important". Please
consult with your team lead before adding this flag.

Cheers,
Tim