and remove usage of RESET MASTER in loops.

- Remove sleep of 0.1 second that was done even when not needed.
- Don't call include/wait_wsrep_ready.inc if NO_WSREP is defined.
- Added NO_WSREP=1 to all atomic tests.
- Use 'select 1' instead of 'show status' to check is server is up.
- Changed RESET MASTER to FLUSH BINARY LOGS to speed up atomic tests.
  To be able to do this, added a new parameter variable to
  show_events.inc to allow one to specify the name of the binary log
  in the output.