Add a filter control to the map
add_filter_control(map, layer_id, filter = NULL, pos = NULL,
rows = 1, cols = 20)A mapboxer object.
The ID of the layer to which the filter is attached.
The initial filter expression.
The position of the control. One of top-left, top-right,
bottom-right or bottom-left.
The number of rows of the textarea input.
The number of columns of the textarea input.