mergetables <old_table> <new_table> <diff_table> <out_table> <out_diff_table>

   <old_table>       "Original" table, taken from a main build or from
                        a previous run of this script.
   <new_table>       New table, taken from an sp of the build for old_table.
   <diff_table>      infdiff.tbl that goes with old_table.
   <out_table>       Location to write the generated table to.
   <out_diff_table>  Location to write the generated diff table to.

Creates an inf data table by combining data from an old build with
data from a service pack.