OSTF-211. New test checks Internet connectivity from the instance has no floatin ip added
	  NManager and SSH client were updated accordingly
OSTF-211. Minor fix after test execution.
OSTF-211: Review comments applied. PEP8 issues fixed.
Merge pull request #79 from Mirantis/ostf-211-Internet_connectivity_check_for_instances_without_floating_IPs

Looks fine for me. Accepted.