skygw_[enable|disable]_log has now been removed from the external
interface and priorities must instead be set using
mxs_log_set_priority_enabled(int priority, bool enabled). A bitmask
is already being updated, but internally and as used by the LOG_IF
macros, the actual enabling is still made using logfile ids.
The configuration entries have been replaced as follows:
log_messages -> log_notice
log_trace -> log_info
The old ones can be used, but cause a warning to be logged.
Similarily the maxadmin commands have been updated.
"[enable|disable] log ..." works as expected, but there will be
a message about it being deprecated. Instead there is now a
[enable|disable] log-priority err|warning|notice|info|debug
command that should be used instead.