Remove mutable state from `ReactiveRedisTemplate`.
Set up required args constructors for passing `RedisSerializationContext` and `ConnectionFactory` while removing `InitializingBean` and `ClassLoaderAware` interfaces forcing the template to hold mutable state.
Introduced some tiny static helpers for creating `RedisSerializationContext` from Serializers and added defaulting.
Moving forward `RedisTemplate` should also be migrated to using the SerializationContext getting rid of mutable state.
Additionally some minor renames, JavaDoc updates and refactored methods to lambda style.
Original Pull Request: #239
07984271d8