Fix bucket tests not failing when testing creation of buckets with invalid names and remove code duplication.
Fix created buckets not deleted when testing creation of buckets with invalid names.
Bad bucket names according to AWS docs (http://docs.aws.amazon.com/AmazonS3/latest/dev/BucketRestrictions.html)
Remove bucket prefix when testing creation of buckets with names starting with a dot or a slash.
Merge branch 'fix_bucket_tests_not_failing' of https://github.com/kto/eutester into kto-fix_bucket_tests_not_failing
fixed bucket names for EUCA-8863, EUCA-8864