Stray CTD point after startup causes issues with "upcast only" data

[richardsc]

First, there is a pressure smoothing setting in SOCIB that likely doesn't need to be applied.

%      PRESSURE_FILTERING: Seabird pressure filtering switch.
%        Boolean setting whether pressure should be filtered with low pass
%        filter described in the Seabird Data Processing Manual.
%        Default value: true
%      PRESSURE_FILTER_CONSTANT: Seabird pressure filter parameter.
%        Non-negative number, the time constant for the Seabird low-pass filter.
%        Default value: 4 (recommended by Seabird Data Processing Manual)

However, one consequence of it is that we discovered a "stray" CTD point that appears when doing upcast-only sampling. The point seems to be caused by the CTD (or payload computer) outputting the last measured point when it is first powered up again. In this case, the last point was near the surface, but now the glider is near the bottom beginning it's "inflect up" cycle and there is a large jump.