maxscale-system-test changed in order to control test environment by itself.
Every test checks which machines are running, compare with list of needed machines
and start new VMs is they are missing in the running machines list.
Tests are executiong MDBCI commands, MDBCI executable should be in the PATH
Some of the scripts assumed that other scripts would be located in the
same directory where the current script was executed.
Also fixed the SSL connection creation which depended on an obsolete
environment variable causing all out-of-source SSL tests to fail.
