Fixed histogram binning issue in splashR

[ssmehta]

Fixes inconsistent histogram generation between the R and Java implementations reported in MassBank/MassBank-data#248.

In splashR, the epsilon correction factor was not applied before converting binned intensities to integers. Without the correction one of the bins was lost due to a floating point artifact in this particular spectrum. I'm surprised that error this did not come up in any of our test sets during validation.