public void addColumn(Column<T, ?> col, String headerString) {
        insertColumn(getColumnCount(), col, headerString);
    }
Adds a column to the end of the table with an associated String header.

@param col          the column to be added
@param headerString the associated header text, as a String
stroom-core-client-widget/src/main/java/com/google/gwt/user/cellview/client/AbstractCellTable.java