Speed up testing

Removed unnecessary sleeps from tests that appear to serve no
purpose. Moveed the kerberos code from the general startup routines to the
kerberos test.

maxscale-system-test/mxs951_utfmb4.cpp

@@ -46,10 +46,7 @@ int main(int argc, char *argv[])
     Test->tprintf("Restart Maxscale");
     Test->restart_maxscale();
 
-    sleep(10);
-
     Test->check_maxscale_alive();
-    //Test->check_maxscale_processes(0);
 
     Test->stop_timeout();
     Test->tprintf("Restore backend configuration\n");