Add file extensions for wiki upload

ppt, pptx, pdf, doc, docx, odt, odp, json, xml

Install/Templates/mediawiki/LocalSettings.php

@@ -149,3 +149,6 @@ wfLoadExtension( 'WikiEditor' );
 
 # Fix login error
 $wgSessionCacheType = CACHE_DB;
+
+# Add file extensions
+$wgFileExtensions = array('ppt', 'pptx', 'pdf', 'doc', 'docx', 'odt', 'odp', 'xml', 'json');