StorageServer class, instead of "ZEO Server:<pid>", use
"StorageServer:<pid>".  In the ZEOServer class, instead of "ZEO
Server:<pid>:<name>", use "ZEOStorage:<pid>:<name>".

Also log a message when a StorageServer instance is created, showing
the pid, the read_only parameter, the storage names, and for each
storage whether it is RO (read-only) or RW (read-write).

Also clean up a few comments, removing one XXX that seems out of
date, and use %r instead of %s in some log messages.