This adds store & forward relays into dendrite for p2p.
A few things have changed:
- new relay api serves new http endpoints for s&f federation
- updated outbound federation queueing which will attempt to forward
using s&f if appropriate
- database entries to track s&f relays for other nodes
* Initial federation sender -> federation API refactoring
* Move base into own package, avoids import cycle
* Fix build errors
* Fix tests
* Add signing key server tables
* Try to fold signing key server into federation API
* Fix dendritejs builds
* Update embedded interfaces
* Fix panic, fix lint error
* Update configs, docker
* Rename some things
* Reuse same keyring on the implementing side
* Fix federation tests, `NewBaseDendrite` can accept freeform options
* Fix build
* Update create_db, configs
* Name tables back
* Don't rename federationsender consumer for now