[visualization-api] Use setValue or setCell on datatable with column id not column index

[John Kilcar]

I'm dynamically creating a datatable based on user choices etc and so can't
entirely predict column index positions but can control the column ids.

support documentation seems to indicate that ids can work instead of column
indexes.

I have been unable to make this work for methods suchs as setCall or
setValue.

Anyone go some sample script of how this can work, or ideas for a work
around.

Thanks in advance