sc_makeClassifier: Make Classifier
In pcahan1/singleCellNet: cell identity from single cell RNA-Seq data

Create a random forest classifier with the transformed training data from query_transform.

1 2	sc_makeClassifier(expTrain, genes, groups, nRand = 70, ntrees = 2000, stratify = FALSE, sampsize = 40)

`expTrain`	transformed training data from `query_transform`
`genes`	vector of gene pairs from `ptGetTop` used as predictors
`groups`	named vector of cells to cancer categories
`nRand`	number of randomized profiles to make
`ntrees`	number of trees to build
`stratify`	whether to use stratified sampling or not
`samplesize`	the samplesize for straified sampling