Earlier, migrateSQLCatalogToERP5Catalog was used only for creating a new ERP5Catalog
and then migrating the objects and properties from sql catalog to this new ERP5 catalog.
This sometimes led to the problem while we install new business templates which do have
Catalog methods. So, the soluton to this is to update this migration function to do the
updation part also. So now we can call this function everytime after we install a BT5
and it'll create/update ERP5Catalog as per needed.

Please note that this hack is not an efficient way to carry this process. Instead the
better option imho(Ayush) is to change completely the BT5 methods structure of handling
Catalog methods which at present time have hardcoded sql_catalog name attached to their
paths.