Is your feature request related to a problem? Please describe.
It would be useful that before trying to start a MS, pyms checks that the configuration is using is valid. I understand that in here

there's some kind of validation. But it seems on high level, it doesn't validate per service, for example.

Describe the solution you'd like
I'd like that every service states clearly its configuration schema and that this can be validated at when starting the microservice.