Add fluent API for ChangeStreams [DATAMONGO-2089]

[spring-projects-issues]

Christoph Strobl opened DATAMONGO-2089 and commented

instead of

Flux changeStream = reactiveTemplate
	.changeStream(newAggregation(match(where("operationType").is("insert"))),
				Person.class, ChangeStreamOptions.empty(), "person");

it would be nice to have a fluent alternative like

reactiveTemplate.listenToChanges() // entry point
  .in("person") // Optional Collection as String or Class
  .as(Jedi.class) // Optional domain type for mapping
  .where(newAggregation(match(where("operationType").is("insert"))) // optional filter query
  .resumeAt() // optional resume token or timestamp
  .stream(); // get the flux

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Referenced from: pull request #751

[spring-projects-issues]

Mark Paluch commented

Added a few comments to the PR