lazr config does not handle schema changes gracefully

[Robert Collins]

lazr config has a very specified schema. As a result, we have to coordinate two rather different actions in a very specific order
 - land a schema change
 - roll out the config entries for it

This causes deployment friction:
 - if we decide to rollback the schema change, we have to rollback the config (not usual practice, can be forgotten)
 - we can't pre-load the config changes, because we have to wait for the new schema to be available
 - our config becomes unpredictably locked to code versions.

I realise this is a designed in feature, however its a choice which adds costs to us. We should instead have a lint step to server start up which logs an OOPS - and then continues. That way when something is wrong, we'll know about it, but deployment/rollbacks won't be affected, and we can prepare for changes in advance rather than having to do them in-sequence with the rollout.

[Gary Poster (gary)]

+1