Test QA264 DHCP lease with routes

Added the set of tests to check DHCP lease, routes and dns setup
Modifications fo older tests

In order to make them fully compatible with the new requirements of the
scenario builder.
Fixed inter vm connectivity test

Corrected a bug in the test, due to the change in how
networks are created now.
Merge pull request #7 from alvico/rebase_QA-264

Test QA264 DHCP lease with routes