Simple screen for outlier cells in a metacell cover, finding genes with overly high expression given their metacell mean

mcell_mc_screen_outliers_1gene_fold(new_mc_id, mc_id, mat_id, T_lfc)

Arguments

new_mc_id: id of new metacell to create
mc_id: ID of metacell in scdb
mat_id: matrix object to use (should be compatible with mc_id)
T_lfc: maximal log2 fold change over the expected to be considered as an outlier.