Use `special-mode' for compilation output

* lisp/org.el (org-compile-file): Switch to `special-mode' for log
  buffer.

Suggested-by: Florian Lindner <mailinglists@xgm.de>
<http://permalink.gmane.org/gmane.emacs.orgmode/112164>

etc/ORG-NEWS

@@ -172,6 +172,7 @@ Simiralry to ~:EXPORT_FILE_NAME:~ property, this keyword allows the
 user to specify the name of the output file upon exporting the
 document.  This also has an effect on publishing.
 **** Horizontal rules are no longer ignored in LaTeX table math mode
+**** Use ~special-mode~ for compilation output
 
 *** ~org-edit-special~ can edit LaTeX environments
 

lisp/org.el

@@ -22462,7 +22462,8 @@ it for output."
 			       (?o . ,(shell-quote-argument out-dir))
 			       (?O . ,(shell-quote-argument output))))))
 	   (dolist (command process)
-	     (shell-command (format-spec command spec) log-buf))))
+	     (shell-command (format-spec command spec) log-buf))
+	   (when log-buf (with-current-buffer log-buf (special-mode)))))
 	(_ (error "No valid command to process %S%s" source err-msg))))
     ;; Check for process failure.  Output file is expected to be
     ;; located in the same directory as SOURCE.