Possible rounding bug in FUV OSM Shift monitors

[jwhite3]

@sahnow noticed that in the FuvOsmShift1Monitor that for some shift values where there is a very small difference between FUVA and FUVB, the difference seems to be being set to 0 by the time the data make it to the plot. It's unclear where this is happening.

This results in some FUVA - FUVB data points being plotted at 0 when they shouldn't be and FUVA vs FUVB data points being plotted on top of each other/

It's been confirmed that this is happening by checking the data directly.

[jwhite3]

This same bug will likely be occurring in all FuvOsmShift monitors.