PAS photodiode plots are all the same

[JustinLangridge]

PAS photodiode waveform plots in the UI are all plotting the same channel currently.

[lo-co]

Bad index in ex.pas.svc.js. The offending code is as follows:

for (var k = 0; k < celldata[0].PhotoDiode.Y.length; k++) {
     var pd = [k*pdt];
     for (var j = 0; j < celldata.length; j++) {
          pd.push(celldata[index].PhotoDiode.Y[k]);
      }

       // Push the data in cell-wise
       PasData.wvfm.pd.push(pd);
}

index should be j