Do not call createContainer(getContainerName)

BaseBlobStoreIntegrationTest.getContainerName implicitly calls
createContainer.
Get container name before creating with metadata
Do not set hash to null unnecessarily

This avoids test failures seen in
CommonSwiftClientLiveTest.testObjectOperations.
Skip testCreateBlobWithExpiry for Swift

jclouds does not implement this functionality.  Now all tests pass for
cloudfiles-us.