tempest_smoketest.sh cleanup and EC2 cli configuration improvements.

- Adding clean up procedure for floating router ports, routers, subnetworks, networks in a tempest tenant in order to prevent tempest test failures in further test runs
- Adding ".eucarc" file for EC2 authoriztion with "tempest" credentials for euca2ools.
- Moved EC2 environment configuration actions from templates to "config.rb" recipe.