LaTeX export: remove the a4paper option from the defaults.

a4paper is no longer a standard option for LaTeX classes

Requested by Hsiu-khuern and many others.

lisp/org-export-latex.el

@@ -86,7 +86,7 @@
 
 (defcustom org-export-latex-classes
   '(("article"
-     "\\documentclass[11pt,a4paper]{article}
+     "\\documentclass[11pt]{article}
 \\usepackage[utf8]{inputenc}
 \\usepackage[T1]{fontenc}
 \\usepackage{graphicx}
@@ -98,7 +98,7 @@
      ("\\paragraph{%s}" . "\\paragraph*{%s}")
      ("\\subparagraph{%s}" . "\\subparagraph*{%s}"))
     ("report"
-     "\\documentclass[11pt,a4paper]{report}
+     "\\documentclass[11pt]{report}
 \\usepackage[utf8]{inputenc}
 \\usepackage[T1]{fontenc}
 \\usepackage{graphicx}
@@ -110,7 +110,7 @@
      ("\\subsection{%s}" . "\\subsection*{%s}")
      ("\\subsubsection{%s}" . "\\subsubsection*{%s}"))
     ("book"
-     "\\documentclass[11pt,a4paper]{book}
+     "\\documentclass[11pt]{book}
 \\usepackage[utf8]{inputenc}
 \\usepackage[T1]{fontenc}
 \\usepackage{graphicx}