Add 'net.discover' method for discovering all vim.Network managed objects
Add 'net.get' vPoller method for getting properties for a single
vim.Network managed object
Add 'net.host.get' vPoller method
Add 'net.vm.get' vPoller method
Rename 'vm.net.discover' method to 'vm.guest.net.get' to make it clean
this is a 'guest' related property
Add 'host.net.get' vPoller method
Add 'vm.net.get' vPoller method
Document new vPoller methods