[8pt] Alaska catchments have multiple IDs after datatype change

[CarsonPruitt-NOAA]

[RyanSpies-NOAA]

Here is the hand 4.8.7.2 inundate nation output for the 50yr flow for the southern Alaska domain showing the erroneous inundation.

[RyanSpies-NOAA]

Branch 0 is producing >9,999 hydroid catchments for these hucs so the int16 4-digit limit is unable to produce unique ids for each hydroid.

[RobHanna-NOAA]

The catchments.tif is also in error for the same reason. Max cell value is 32,676. The catchments tif cells have an int16 dtype, but some hydro_ids go beyond 32,767, which is the max value that can be stored as an int16. This can be seen at 4_8_7_2 /19020504/branches/0/gw_catchments_reaches_filtered_addedAttributes_0.tif. This might be a significant problem for our pending FIM 6.0 release.