implement ResultSet findColumn() method issue#525

[dangerous1990]

    /**
     * Maps the given <code>ResultSet</code> column label to its
     * <code>ResultSet</code> column index.
     *
     * @param columnLabel the label for the column specified with the SQL AS clause.  If the SQL AS clause was not specified, then the label is the name of the column
     * @return the column index of the given column name
     * @exception SQLException if the <code>ResultSet</code> object
     * does not contain a column labeled <code>columnLabel</code>, a database access error occurs
     *  or this method is called on a closed result set
     */
    int findColumn(String columnLabel) throws SQLException;

[zhicwu]

Could you change target to develop and add unit tests accordingly?

[dangerous1990]

Could you change target to develop and add unit tests accordingly?

done