Add GRANT as known statement.

Author: udan11

src/Parser.php

@@ -40,6 +40,7 @@ class Parser
         'HELP'              => '',
         'USE'               => '',
         'STATUS'            => '',
+        'GRANT'             => '',
 
         // Table Maintenance Statements
         // https://dev.mysql.com/doc/refman/5.7/en/table-maintenance-sql.html