Merge pull request #11 from AppScale/testing

sync with main branch
Merge github.com:AppScale/appscale-tools
Fix to let enable root login to retry, fixes errors on EC2 during appscale up
Merge branch 'testing' of github.com:AppScale/appscale-tools into fix-enable-root-login-to-retry
unit tests fixed
unit tests fixed
Merge pull request #240 from briandrawert/fix-enable-root-login-to-retry

Fix enable root login to retry