Docs: Updated changelog

Author: rozza

docs/reference/content/changelog.md

@@ -22,6 +22,7 @@ Changes in Version 3.1.0
  : [CASBAH-186](https://jira.mongodb.org/browse/CASBAH-186)
  * Added support for bypassDocumentValidation : [CASBAH-187](https://jira.mongodb.org/browse/CASBAH-187)
  * Added support for WriteConcern with findAndModify helpers : [CASBAH-188](https://jira.mongodb.org/browse/CASBAH-188)
+ * Added dot notation in get / getAs methods for convenience : [CASBAH-190](https://jira.mongodb.org/browse/CASBAH-190)
 
 Changes in Version 3.0.0
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