bump nginx-mantlui container to 0.7.2 
bump nginx-mantlui container to 0.7.2 

mesos ui continually says "unable to connect to <mantl controller:443>"
mesos itself is running fine and marathon has no problem.

/var/log/nginx/error.log
2016/12/01 18:53:59 [emerg] 399#0: no servers are inside upstream in /etc/nginx/nginx.conf:36

This is fixed by the Aug 22 commit to nginx-mantlui
https://github.com/CiscoCloud/nginx-mantlui/blob/master/nginx.tmpl

which is included in the 0.7.2 nginx-mantlui container
mantl/mantl,CiscoCloud/microservices-infrastructure,KaGeN101/mantl,mantl/mantl,CiscoCloud/mantl,CiscoCloud/microservices-infrastructure,KaGeN101/mantl,CiscoCloud/mantl