org-export: Allow nested footnotes (part 2)
* EXPERIMENTAL/org-e-latex.el (org-e-latex-footnote-reference):
Correctly handle numbering with nested footnotes.
* contrib/lisp/org-element.el (org-element-map): Apply function to
element or object before applying it to its secondary string, if
any. Otherwise, linearity is broken.
* contrib/lisp/org-export.el (org-export-footnote-first-reference-p,
org-export-get-footnote-number): Take care of recursive footnotes.
(org-export-get-genealogy): Correctly get genealogy of an item within
a secondary string.
* testing/contrib/lisp/test-org-export.el: Add tests.