1.14 release notes: Relative to 1.10, describe experimental changes
* docs/release-notes/1.14.html (new-feature-compatibility-table): Add rows the experimental shelving, commit checkpointing, and viewspec output features. (shelving-transition, checkpointing, shelving, viewspec-output): New subsections. Text is (mostly) copied from the 1.11 through 1.13 release notes, with some edits. Notably, document that while the shelving feature can handle more types of changes than in 1.10, it is reportedly slower than in 1.10.