log message clarifications

[jokjr]

1. It would be nice if the certgrinder x.yy.z running, log-level is ABC log message could include information to identify the client, like the reported SSH ip address.

2. It would also be nice if the Certificate SAN list is different from the expected message could state the difference between the current (on-disk certificate) and the expected domainsets. perhaps something like

f"to-be-added: {set(expected).difference(set(ondisk)) } to-be-removed: { set(ondisk).difference(set(expected)) }"