Irdest spec, db, route scoring

Performant ad hoc mesh networks are an important way to achieve more resilience and reduce the dependency on fixed infrastructure. Irdest is a mature, relevant and up-to-date effort for hardware- and end-user-agnostic mesh networking. This project tackles some of the largest remaining issues in the Irdest stack. The Ratman router is currently not yet usable in production settings without immense supervision. The main goal of this project is to elevate the quality and resilience of Ratman to reach a level that users, who are not directly involved in development, have the capacity to run an instance and get reasonable error messages when something goes wrong - while minimising the amount of intervention actually required. Additional implementation of a few key missing features will make Ratman more useful in a wider set of deployments, and should improve general performance and uptime.