new module with runtime security checks, it will also check and do

* libxslt/security.[ch] libxslt/Makefile.am: new module with
  runtime security checks, it will also check and do directory
  creation when allowed
* libxslt/documents.c libxslt/imports.c libxslt/transform.c
  libxslt/xslt.c libxslt/xsltInternals.h: plug-in the new
  security infrastructure probes at file reading or file creation
* xsltproc/xsltproc.c: plugged the security module there too,
  added the new options --nowrite and --nomkdir
* doc/*: updated the man page and regenerated.
Daniel

doc/html/libxslt-xsltinternals.html

@@ -1084,6 +1084,7 @@ CLASS="PROGRAMLISTING"
     xsltRuntimeExtraPtr extras;		/* extra per runtime informations */
 
     xsltDocumentPtr  styleList;		/* the stylesheet docs list */
+    void                 * sec;		/* the security preferences if any */
 };</PRE
 ></TD
 ></TR