Transform SNS elements and move them to the alias stack.

[HyperBrain]

Closes #43

SNS Topics and subscriptions are now part of the alias, i.e. the topic name is appended with the alias name and the lambda subscriptions point to the associated function aliases.
This solution follows the discussion in #43

[coveralls]

Coverage increased (+0.01%) to 49.783% when pulling 9e2728f on support-sns-events into 36e8259 on master.

[coveralls]

Coverage increased (+2.3%) to 52.056% when pulling 1fbc72b on support-sns-events into 36e8259 on master.