org-odt.el: Make LibreOffice the default converter

* lisp/org-lparse.el (org-lparse-do-convert): Replace
`call-process' with `shell-command-to-string'.

* lisp/org-odt.el (org-export-odt-convert-processes): Add a new
converter which depends solely on LibreOffice and nothing
else.
(org-export-odt-convert-process): Make the above native
converter the default.

Thanks to Giles for introducing the "--convert-to" option of
soffice.exe.  The option seems to be a fairly recent
development.

http://imperfectsoftware.blogspot.in/2012/01/one-of-my-less-enjoyable-tasks-is-to.html

With this change, one can export to pdf via odt by a simple
  (setq org-export-odt-preferred-output-format "pdf")
There is no need to install additional converters.

lisp/org-lparse.el

@@ -493,28 +493,29 @@ This is a helper routine for interactive use."
 	 (out-dir (file-name-directory in-file))
 	 (arglist (mapcar (lambda (arg)
 			    (format-spec
-			     arg `((?i . ,in-file)
+			     arg `((?i . ,(shell-quote-argument in-file))
 				   (?I . ,(browse-url-file-url in-file))
 				   (?f . ,out-fmt)
 				   (?o . ,out-file)
 				   (?O . ,(browse-url-file-url out-file))
-				   (?d . ,out-dir)
+				   (?d . , (shell-quote-argument out-dir))
 				   (?D . ,(browse-url-file-url out-dir)))))
-			  (cdr convert-process))))
+			  convert-process))
+	 (cmd (mapconcat 'identity arglist " ")))
     (when (file-exists-p out-file)
       (delete-file out-file))
 
-    (message "Executing %s %s" program (mapconcat 'identity arglist " "))
-    (apply 'call-process program nil nil nil arglist)
+    (message "Executing %s" cmd)
+    (let ((cmd-output (shell-command-to-string cmd)))
+      (message "%s" cmd-output))
+
     (cond
      ((file-exists-p out-file)
       (message "Exported to %s using %s" out-file program)
       (when prefix-arg
 	(message "Opening %s..."  out-file)
 	(org-open-file out-file))
-      out-file
-      ;; (set-buffer (find-file-noselect out-file))
-      )
+      out-file)
      (t
       (message "Export to %s failed" out-file)
       nil))))

lisp/org-odt.el

@@ -2402,8 +2402,10 @@ visually."
       (replace-match ""))))
 
 (defcustom org-export-odt-convert-processes
-  '(("BasicODConverter"
-     ("soffice" "-norestore" "-invisible" "-headless"
+  '(("LibreOffice"
+     ("soffice" "--headless" "--convert-to %f" "--outdir %d" "%i"))
+    ("BasicODConverter"
+     ("soffice" "--headless"
       "\"macro:///BasicODConverter.Main.Convert(%I,%f,%O)\""))
     ("unoconv"
      ("unoconv" "-f" "%f" "-o" "%d" "%i")))
@@ -2436,7 +2438,7 @@ they are interpreted as below:
 	   :value-type (group (cons (string :tag "Executable")
 				    (repeat (string :tag "Command line args")))))))
 
-(defcustom org-export-odt-convert-process nil
+(defcustom org-export-odt-convert-process "LibreOffice"
   "Use this converter to convert from \"odt\" format to other formats.
 During customization, the list of converter names are populated
 from `org-export-odt-convert-processes'."