BrenneckeGetVariableGenes
                        Identify Highly Variable Genes
M3DropCleanData         Filter Expression Data
M3DropDifferentialExpression
                        Differentially Expressed Genes.
M3DropDropoutModels     Fit functions to the dropouts vs expression
                        distribution.
M3DropExpressionHeatmap
                        Plot Heatmap of Gene Expression
M3DropGetExtremes       Get outliers from MM curve.
M3DropGetHeatmapCellClusters
                        Extracts cell clusters from heatmap output
M3DropGetMarkers        Identify marker genes
M3DropTestShift         Test for horizontal shift.
M3DropThreeSetVenn      Three-way Venn Diagram
bg__fit_MM              Fit functions to the dropouts vs expression
                        distribution.
