Update 2.13.1 release notes
Update 2.13.1 release notes

Change-Id: I63cc731167722bec67815c2fb160ec3b2acda037

qtproject/qtqa-gerrit,gerrit-review/gerrit,qtproject/qtqa-gerrit,GerritCodeReview/gerrit,qtproject/qtqa-gerrit,gerrit-review/gerrit,GerritCodeReview/gerrit,gerrit-review/gerrit,GerritCodeReview/gerrit,GerritCodeReview/gerrit,WANdisco/gerrit,WANdisco/gerrit,WANdisco/gerrit,gerrit-review/gerrit,WANdisco/gerrit,qtproject/qtqa-gerrit,GerritCodeReview/gerrit,qtproject/qtqa-gerrit,qtproject/qtqa-gerrit,gerrit-review/gerrit,WANdisco/gerrit,GerritCodeReview/gerrit,WANdisco/gerrit,WANdisco/gerrit,GerritCodeReview/gerrit,qtproject/qtqa-gerrit,gerrit-review/gerrit,GerritCodeReview/gerrit,gerrit-review/gerrit