Merge pull request #181 from daniellemayne/develop

folder support
FB4966: Allow tags with null value to be set as empty tags
FB4966: Allow tags with null value to be set as empty tags
Merge branch 'develop' of https://github.com/maksimov/dasein-cloud-aws into develop
Merge pull request #183 from maksimov/develop

FB4966: Allow tags with null value to be set as empty tags