Emacs's bc511a64f6d made tree-wide changes to prefer https to http.
For Org, this resulted in the header of every lisp/*.el file being
changed. Make the same changes in lisp/*.el files that were added
since Org version 9.0.10 (the last version that was synced with
Emacs).
* lisp/ob-vala.el: Add support for the Vala language to Babel.
* testing/lisp/test-ob-vala.el: Add tests for ob-vala.el.
* doc/org.texi (Working with source code): Add Vala to the list of
supported languages.