added range and name validations for networks and subnets configuration (management and templates).
Avoid NPE
Initiate tests for validations
Fix assign floating ip on network driver. Sometimes the driver took a wrong port id leading not to be able to assign floating ip.
Force assign floating ip when using only management network (if assign floating ip option is on)
added validation and unit tests. (networks, formats, credentials...etc)....
Merge branch 'openstack-driver-computeNetwork' of https://github.com/fastconnect/cloudify into openstack-driver-computeNetwork
Fix tests
Merge pull request #90 from fastconnect/openstack-driver-computeNetwork

Enhance Openstack driver to avoid NPE and add validations