Expand `CorrelationDataProvider` section

[smcvb]

The Correlation Data Providers would benefit from some additional information. Things like:

• Listing the provided implementations
• Describe the intent of these implementations
• Specify how to configure several CorrelationDataProviders in Spring (Boot)
• Providing a custom sample that inserts fields from some static context.
• Define how this can be paired up with a MessageDispatchInterceptor to add MetaData fields for the first message in the chain