Synchronize cache with chain

[bedeho]

Right now, if some content is set as unpublished or if a data object is just outright deleted, or if there is some moderation going on, as will be unlocked by https://github.com/Joystream/joystream/issues/2760. The Argus cache is not synchronized with this currently. This is a problem, because there can be quite substantial urgency in content delivery policy mirroring the state of the chain, for example in being responsive to removal of out-of-policy content. This synch has to work both while node is operating, but also if its booting up and trying to continue with pre-existing cache.