improved error message a little

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@6863 20353a03-c40f-0410-a6d1-a30d3c3de9de

bt5/erp5_forge/SkinTemplateItem/portal_skins/erp5_svn/BusinessTemplate_doSvnMultiDiff.xml

@@ -77,7 +77,7 @@ if \'uids\' not in context.REQUEST.keys():  \n
 revisions_list = context.REQUEST[\'uids\']\n
 \n
 if len(revisions_list) != 2:\n
-  context.REQUEST.set(\'portal_status_message\', \'You must select only TWO revisions!\')\n
+  context.REQUEST.set(\'portal_status_message\', \'You must select exactly TWO revisions!\')\n
   return context.asContext(file=file).BusinessTemplate_viewSvnLog()\n
 \n
 revisions_list.sort()\n