Feature request: Allow global variables to avoid duplication

[gwd]

I have a dozen sqlite databases, all with the same properties: retention 600h, snapshot-interval 24h, alternate s3 endpoint, etc. As far as I can tell, at the moment the only way to apply the same properties to all 12 databases is to copy identical values to all 12 databases.

It would be nice if I could specify at the top level that the default retention is 600h, default snapshot-interval is 24h, default s3 endpoint is XXX, so that I don't have to c&p the same information 12 times. (Similar behavior to access-key-id and secret-access-key.)

[hifi]

I think this is a good idea to be able to set top level defaults.