* lisp/ox-latex.el (org-latex-src-block, org-latex-keyword,
org-latex-inline-src-block, org-latex-template,
org-latex--caption/label-string, org-latex-engraved-preamble,
org-latex-listings): Replace `org-latex-listings' with
`org-latex-src-block-backend', which now can be set to listings/verbatim
and no longer advertises t/nil as valid values.
* lisp/ox-beamer.el (org-beamer-template): Update in the same manner as
`org-latex-template'.
* lisp/org-compat.el: Make `org-latex-listings' an obsolete alias for
`org-latex-src-block-backend'.
* testing/lisp/test-ox.el: Replace `org-latex-listings' reference with
`org-latex-src-block-backend'.
* doc/org-manual.org (Footnotes, LaTeX specific properties, Literal
Examples): Replace references to `org-latex-listings' with
`org-latex-src-block-backend'.
* etc/ORG-NEWS: Add a news entry noting this change.
The variable `org-latex-listings' originally indicated whether source
blocks should use the listings LaTeX package, or not. This usage has
evolved over the years, and now it sets one of four different
fontification backends. This renaming should make the variable name a
bit less misleading.
b4e4b3c502
