PLATFORM-535 Add sanitizer for S3 bucket names in CreateNewWiki

This PR addresses the issue with bucket names and ensures the newly created buckets will have names compatible with both S3 and Swift APIs. The process to create a new bucket name appears only in CreateNewWiki so that place should be sufficient to resolve the issue.

https://wikia-inc.atlassian.net/browse/PLATFORM-535

It is a work in progress.


/cc @Wikia/platform-team @nandy
Yes. Documentation is good, but self documenting code is better. This is a case in point that readers of code don't tend to trust the documentation as much as they do the code. Also, if you change `55` to something else here it also means that you need to change it there too.