Improve diagnostic info when lib/.deploy is deemed invalid

[atomicstack]

git-deploy status et al emit a somewhat useless "# WARN : The deploy file <lib/.deploy> is not valid" warning when HEAD points somewhere different than the SHA1 stored inside lib/.deploy.

We should probably improve this (even if it just means adding a warning like "Has somebody modified the repo without starting a rollout?"), as it seems to cause Fear and Loathing for people who encounter it when about to deploy.

[atomicstack]

Warnings squashed by commit 5e28738; will merge if there are no objections.

[demerphq]

did you merge this? can we close the issue?

[burak]

Looks like it wasn't merged as I saw this stuff recently. Where does it merged into btw?