[#1322] DOC: update release notes for switch from Bintray jcenter to Maven Central

Author: remkop

RELEASE-NOTES.md

@@ -72,6 +72,7 @@ Picocli follows [semantic versioning](http://semver.org/).
 * [#1330] BUILD: use type-safe DSL instead of direct XML manipulation to generate `pom.xml`. Thanks to [Fiouz](https://github.com/Fiouz) for the pull request.
 * [#1332] BUILD: Bumping asciidoctor + asciidoctor gradle plugin to latest versions. Thanks to [Andreas Deininger](https://github.com/deining) for the pull request.
 * [#1413] BUILD: Improve Travis CI build Performance. Thanks to [YunLemon](https://github.com/YunLemon) for the pull request.
+* [#1322] BUILD: switch from Bintray jcenter to Maven Central.
 
 ## <a name="4.6.2-deprecated"></a> Deprecations
 No features were deprecated in this release.