Fix several issues with gm_report

Enjoy Scigenex...

Refactored usage of do.call() in gm_report().

Added population percentage to gm_report()

Adding pop stats by origin in gm_report().

Various minor modif including split.by in Dimplot

Still improving gm_report()x

Fix issue with percent.mt.

Added PCA, elbow and modified table outout of gm_report().

Introducing sampling in interactive heatmap of gm_report().