nodemgr: detect pod type by container's Env
nodemgr: detect pod type by container's Env

Change-Id: I15894e186439ac7b317a0d54fcda070e16e436c8
Partial-Bug: #1759937

eonpatapon/contrail-controller,rombie/contrail-controller,eonpatapon/contrail-controller,rombie/contrail-controller,rombie/contrail-controller,rombie/contrail-controller,rombie/contrail-controller,eonpatapon/contrail-controller,rombie/contrail-controller,rombie/contrail-controller,eonpatapon/contrail-controller,eonpatapon/contrail-controller,eonpatapon/contrail-controller,eonpatapon/contrail-controller