Add flag to command to generate routes without the server

[carnage]

We generate hosted and hostless routes based solely on the data in the openapi file, quite often this comes with servers that are either wrong or only applicable for a production environment.

It would be useful to be able to override this at route generation time, using a flag on the command.

After this is implemented, there will be three possible behaviours:

• Generate using only servers/paths from the openapi spec file (current behaviour)
• Ignore servers entirely and only generate the hostless version
• Generate using the servers in the openapi spec file but also add a fallback hostless option to the router