Update vHello_Tacker for Danube
JIRA: MODELS-23
Verified on devstack.
Use current xenial cloud image link.
Tests as part of asserts are not working - refactor.
Correct URL for OPNFV logo.
Fix if statements as needed.
Loop on VNF deletion (response is 0 so can't use that
as success indication).
Increase VNF creation loop timeout.
Use presence of dockerenv as "running in container" indication.
Change-Id: I7cdc0719b1d5bac7cfb90efed9a8ce092a63ec86
Signed-off-by: Bryan Sullivan <bryan.sullivan@att.com>