Adding option mysqldump --no-data-med

Some users have reported differences moving from FederatedX to Spider , mysqldump is not exporting rows from federated.

if (!opt_no_data &&

       (!my_strcasecmp(&my_charset_latin1, table_type, "MRG_MyISAM") ||

        !strcmp(table_type,"MRG_ISAM") ||

        !strcmp(table_type,"CONNECT") ||

        !strcmp(table_type,"FEDERATED")))

     result= IGNORE_DATA;

 } 

There is probably a better way to list all med engine directly in the code, can't we add a flag to storage engine API

This task would add OQGRAPH and SPIDER test and an additional option

'm' short option is not use

 {"no-data-med", 'm', "No row information for MED storage.", &opt_no_data_med,

   &opt_no_data-med, 0, GET_BOOL, NO_ARG, 1, 0, 0, 0, 0, 0},

The default would not fetch federated rows