* Rename serverkeyapi to signingkeyserver
We use "api" for public facing stuff and "server" for internal stuff.
As the server key API is internal only, we call it 'signing key server',
which also clarifies the type of key (as opposed to TLS keys, E2E keys, etc)
* Convert docker/scripts to use signing-key-server
* Rename missed bits
* Initial pass at refactoring config (not finished)
* Don't forget current state and EDU servers
* More shifting around
* Update server key API tests
* Fix roomserver test
* Fix more tests
* Further tweaks
* Fix current state server test (sort of)
* Maybe fix appservices
* Fix client API test
* Include database connection string in database options
* Fix sync API build
* Update config test
* Fix unit tests
* Fix federation sender build
* Fix gobind build
* Set Listen address for all services in HTTP monolith mode
* Validate config, reinstate appservice derived in directory, tweaks
* Tweak federation API test
* Set MaxOpenConnections/MaxIdleConnections to previous values
* Update generate-config
