"IBDRemove.R". if QCresult(seqfile)$MissingRate is missing, recalculate the missing rate by opening the gfile connection.
todo: if missing, then run seqfile <- MissingRate(seqfile) and extract the missing rate info. -- done!
"plotInbreeding", interactive, xlab, ylab, refer to plotSexCheck. -- done.
"dataset_docum.R". to document all files that are under inst/extdata/... -- done for all 5 files. (except "sampleQCreport.Rmd" and "metadata.csv")
"PCACheck.R", add an argumnent of "npcs=4" for the # of pc axis to use for pop prediction in SVM. -- done.