Follow up work for RUBY-1871 Trying to check in a connection which is not currently checked out by this pool.

Review and improve as necessary CMAP diagnostics to help with troubleshooting of connection pool-related issues:
1. Review cmap event logger output when a server is removed and readded - is it clear which connections go with which pool?
2. Based on results of previous point, possibly revise documented cmap listener guidance to log additional information.
3. Go through exceptions raised in connection/conn pool code and ensure all are labeled with address and/or pool and/or generation as needed to aid in diagnostics.