5.14.0 release notes (#14245)

* 5.14.0 release notes: raw from script

* 5.14.0 release notes: add boilerplate

* sorting misc and deleting 5.13 commits

* fixing up contributors

* fixing up gitlab issues titles

* annotating

* rearranging sections

* editing and clean up

* 5.14.0 release notes: edits

* 5.14.0 release notes: incorporated late changes