Due to incorrect SSL certs copying to backend and wrong setting in
maxscale.cnf it was not possible to active backend SSL.
Additionally, one more maxscale restart added to 'sql_queries' test
to reproduce SSL bug in 2.4.1.
Also ssl.cnf tuned in order to reproduce SSL bug
When a test is checking the status of the nodes, the output is relatively
verbose.
Also changed dropping of users to use the IF EXISTS syntax. This will
remove the errors if the users do not exist.
The users are now created on both the slaves as well as the master. This
allows static binlog coordinates to be used on the slaves and the
replication initialization boils down to a set of SQL queries.
