clean up / update org article, latex preamble and template

settings/org-settings.el

@@ -249,6 +249,7 @@ Example defines
   :load-path (lambda () (list (concat config-dir "lisp/org")))
   :delight (org-mode "Org")  ;; "Org " "\u01F15E"
   :defer t
+  ;;:bind (("C-c <del>" . org-mark-ring-goto))  ;; normally at C-c & but it is redefined by yasnippet
   :init
   (setq org-export-backends '(ascii html icalendar latex md odt reveal tufte))
   :config
@@ -912,7 +913,7 @@ Uses function `my-org-headline-string-element'"
   (setq org-latex-bib-compiler "biber")  ;; %bib in org-latex-pdf-process
   (setq org-latex-pdf-process
         (if (executable-find "latexmk")
-            '("latexmk -f -pdf -%latex -interaction=nonstopmode -output-directory=%o %f")
+            '("latexmk -f -pdf -%latex -shell-escape -interaction=nonstopmode -output-directory=%o %f")
           (cond ((string-equal org-latex-compiler "lualatex")
                  '("lualatex --interaction=nonstopmode --output-directory=%o %f"
                    "biber %b"