minor #1874 Update changelog (XWB)

This PR was merged into the 2.3-dev branch.

Discussion
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Update changelog

@xabbuh Not sure if the next release should be 2.3.1 or 2.4?

Commits
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198348e Update changelog

Author: xabbuh

CHANGELOG.md

@@ -1,6 +1,23 @@
 CHANGELOG
 =========
 
+2.x.x
+-----
+
+* improved Symfony 4 compatibility
+
+* manually decorate the core JMS handler registry
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+* run checks after SensioFrameworkExtraBundle
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+* made the view handler alias public
+
+* check for definitions before they might be removed
+
+* added Yaml routing resource support
+
+* refactored several unit tests
+
 2.3.0
 -----