* contrib/lisp/org-export.el (org-export-define-backend): Update
docstring.
(org-export-special-keywords): Remove "MACRO".
(org-export--get-inbuffer-options, org-export--get-buffer-attributes):
Remove internal macro handling.
(org-export-as): Use external tool instead.
(org-export-expand-macro): Remove function.
* contrib/lisp/org-e-ascii.el (org-e-ascii-macro): Remove function.
* contrib/lisp/org-e-groff.el (org-e-groff-macro): Remove function.
* contrib/lisp/org-e-html.el (org-e-html-macro): Remove function.
* contrib/lisp/org-e-latex.el (org-e-latex-macro): Remove function.
* contrib/lisp/org-e-man.el (org-e-man-macro): Remove function.
* contrib/lisp/org-e-odt.el (org-e-odt-macro): Remove function.
* contrib/lisp/org-e-texinfo.el (org-e-texinfo-macro): Remove
function.
* testing/lisp/test-org-export.el: Remove tests.
Since macros are now expanded before parsing (and produce Org syntax),
back-ends will never see them (unless NO-EXPAND argument from
`org-export-as' is non-nil, which isn't the case for any back-end so
far).
* lisp/org-element.el (org-element-link-type-is-file): New variable.
(org-element-link-parser): Extract search option and application in
"file"-type links.
* contrib/lisp/org-e-html.el (org-e-html-link): Remove components
extraction since this in now done in `org-element-link-parser'.
* contrib/lisp/org-e-odt.el: Remove components extraction since this
in now done in `org-element-link-parser'.
* contrib/lisp/org-e-texinfo.el (org-e-texinfo-link): Remove
components extraction since this in now done in
`org-element-link-parser'.
* contrib/lisp/org-e-latex.el (org-e-latex-link): Remove components
extraction since this in now done in `org-element-link-parser'.
* contrib/lisp/org-e-man.el (org-e-man-link): Remove components
extraction since this in now done in `org-element-link-parser'.
* contrib/lisp/org-e-groff.el (org-e-groff-link): Remove components
extraction since this in now done in `org-element-link-parser'.
* contrib/lisp/org-md.el (org-md-link): Remove components extraction
since this in now done in `org-element-link-parser'.
* testing/lisp/test-org-element.el: Add tests.
* org-e-groff.el (org-e-groff-item): Removed the `counter' variable from let assignment list.
(org-e-groff-table--align-string): Removed the `attr' and `align' variables from the list assignment list.
* org-e-man.el (org-e-man-item): Removed the `counter' variable from the let assignment list.
(org-e-man-src-block): Removed non needed formatting string that was causing formatting errors for source blocks.
(org-e-man-table--align-string): Removed `attr' and `align' variables from the let assignment list.
* contrib/lisp/org-e-man.el (org-e-man-headline): Fixed call to org-export-first-sibling-p and org-export-last-sibling-p
(org-e-man-table-cell): Fixed call to org-export-get-next-element