Make sure collocation_index is 0..N-1 when using two resampling operations as part of matchup
Make sure collocation_index is 0..N-1 when using two resampling operations as part of matchup

When performing a 'harpcollocate matchup' and providing two resampling operations (one on each dataset) the final collocation result file could have gaps in the collocation_index range. This is now no longer the case.

stcorp/harp,stcorp/harp,stcorp/harp,stcorp/harp,stcorp/harp,stcorp/harp