RT feature analysis display

[joslloand]

Integrate @mtmccrea development.

Also related to #6

[mtmccrea]

Note: this requires an addition to the SC source. In the near term, it needs to be tested in-house before putting in the SC pull request, because once the display code (how data is drawn in the various scopes) is in the SC source, it lives in their release cycle. We'd still be able to change the higher level interface (QT) elements and the signal pre-processing which happens in the class side.

[joslloand]

Given the inclusion of FoaAnalyze, some visualizations may be convenient to demonstrate via the existing interface for Stethoscope.

Ideally, we'd like to be able to plot spherical heat maps. (Would this be possible with PointView?)