Fix bug that popped up when creating security group rules with -port=>0.
Merge pull request #18 from miquelruiz/master

Support for scaling policies
add support for OpenStack as suggested by https://github.com/lstein/LibVM-EC2-Perl/issues/15; not sure if this is the right fix
Autoscaling tests out of SKIP block

Some tests were out of the SKIP block, making them fail when the credentials
were not supplied.