What's Changed
* refactor constants by kulapard in https://github.com/kulapard/apispec-aiohttp/pull/31
* use a unique prefix for all app keys (`web.AppKey`) by kulapard in https://github.com/kulapard/apispec-aiohttp/pull/32
**Full Changelog**: https://github.com/kulapard/apispec-aiohttp/compare/0.4.1...0.4.2