More assertions for test_integration_1

For the boto/test_ec2_instance_run.py test_integration_1 test
add assertions to check that the security group modifications
and public ip association calls actually succeed.

This is to help debug the intermittent bug 1117555 which appears
to be due to the instance sometimes being unreachable via its
public ip.

Change-Id: I8c1ffeee62e1021ecf24f05ac26518ced640c5a1
Merge "More assertions for test_integration_1"