Used in conjunction with newAndUpdated plugin.

Display new listings that were added in the previous 'x' days.  The value can be quite flexible.  For instance, these all work:

[rover_idx_plugin plugin_type="newAndUpdated" date_added="1 month"]

[rover_idx_plugin plugin_type="newAndUpdated" date_added="4 days"]

[rover_idx_plugin plugin_type="newAndUpdated" date_added="2 weeks"]

Default is to ignore this parameter, in favor of prev_days="7 days".