flask blueprint naming clash

[elmanm]

I haven't tested this with other handler integrations but in the flask integration, because the Blueprint is created with a hardcoded name "swagger_blueprint", you can't add ui more than once (e.g. if you have have multiple specifications for different versions), because each Blueprint must have a unique name.

It would be nice if the name was derived from the ApplicationDocument.title or ApplicationDocument.url_prefix, so it can be set per document if needed.

[PWZER]

There could be a problem，thank you for your advice.