Changes in vimconn_vmware.py : Modified flavor logic as per Code review comments.

Fixed defect – 167 VMware connector needs to resolve vCenter host name.
Fixed defect – 185 Plug test - Communication to VMware VIM does not work unless hostnames are added to /etc./hosts in RO”

Change-Id: Ibd83a870b4b086c4bd2d804e711adbf1c8cbb184
Signed-off-by: kate <akate@vmware.com>