Change the Readme.txt for Wiris Math editor for correct configuration due it supports now a chamilo installation

main/inc/lib/javascript/ckeditor/plugins/ckeditor_wiris/Readme.txt

@@ -3,3 +3,8 @@ Download the Plugin from here :
 http://www.wiris.com/es/plugins3/ckeditor/download
 and place the resulting folder inside
 main/inc/lib/javascript/ckeditor/plugins/
+
+To configure the plugin you need to assign read and write permissions to the cache and formulas directories inside the plugin or rename the configuration.ini.dist to configuration.ini and uncomment this lines if you want to change the place where stored the formula images :
+
+#wiriscachedirectory = /var/cache
+#wirisformuladirectory = /var/formulas