* reduce async sleep time in test
* make zypper test less destructive (don't break following uses of zypper)
* fix ca cert on suse
* fix/enable postgres/mysql on opensuseleap
* fix mysql test for mysql versions 5.7.6 and newer
* skip sni_host check on ubuntu1604
* add HTTPTESTER flag for test_uri
ubuntu 16.04 uses dash which drops env variables containing a dot
we work around this by adding an explicit env variable to enable httptester
