Add description of profiles to OSTF Contributor`s Guide

Added description on how to use __profile__ dictionary
for setup of test sets.

Change-Id: I5da19861793928a98f602f11e6a13232e8ec1302
Closes-Bug: #1301286
vCenter integration UI added
removed kvm and qemu hypervisors for custom CentOS release
changed the vcenter UI, added dependencies, removed separate release
vcenter integration UI refactored
added dependency. neutron option will be not available with vcenter
Disable Neureton for vCenter
added hypervisor panel deps for network panel