Refine `JedisConnectionFactory`

General code refactoring and cleanup task triggered while considering the fallout and possible workaround for #2738.

Introduces private (static) methods (and/or local variables) to simplify and remove duplicate logic while simultaneously removing broken line breaks affecting readability and understanding.

NOTE: line breaks are also being affected by our excessive indentation.

Simplifies assertions by making consistent use of Spring Frameworks Assert facility rather than unnecessary conditional blocks.

Refers to state variables using getter (rather than direct variable reference) where applicable helping to improve extensibility.

Reorganizes state variables in both JedisConnectionFactory as well as MutableJedisClientConfiguration by type in alphabetical order.

Organizes code according to Spring Data source code guidelines (e.g. private methods towards the end of classes).

Deprecates createTopologyProvider(..) in favor of createClusterTopologyProvider(..) for consistent and clarified naming.

Adds additional and judicious white space to improve readability.