public void insertColumn(int beforeIndex, Column<T, ?> col, String headerString,
                             String footerString) {
        insertColumn(beforeIndex, col, new TextHeader(headerString), new TextHeader(footerString));
    }
Inserts a column into the table at the specified index with an associated
String header and footer.

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