GUACAMOLE-708: Add and update JavaDoc comments.

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-mysql/src/main/java/org/apache/guacamole/auth/mysql/conf/MySQLGuacamoleProperties.java

@@ -241,6 +241,11 @@ public class MySQLGuacamoleProperties {
         
     };
     
+    /**
+     * Wether or not to automatically create accounts in the MySQL database for
+     * users who successfully authenticate through another extension.  By
+     * default users will not be automatically created.
+     */
     public static final BooleanGuacamoleProperty MYSQL_AUTO_CREATE_ACCOUNTS =
             new BooleanGuacamoleProperty() {