[yt-dev] Issue #719: Remove all references to PlotCollection (yt_analysis/yt)

New issue 719: Remove all references to PlotCollection https://bitbucket.org/yt_analysis/yt/issue/719/remove-all-references-to-plot... Cameron Hummels: Now that PlotCollection has been phased out, we need to remove all the references in the docs to them, and substitute them with the appropriate replacement functions: SlicePlot, ProjectionPlot, PhasePlot, etc. @MatthewTurk or @ngoldbaum are either of you up for this?