Due to missing information from the node owner API, only syncing would often be displayed during blockchain synchronization.
Because of this, I expanded the owner API (server_api.rs).
Now all necessary data is provided via the API. This allows the display to be calculated as in the CLI.
This expansion should also be implemented in the Grin++ API.
In addition, all peers can now be displayed and filtered.
Banning and unbanning also work.
