FormatRocrObjects: Formats predictions into a ROCR 'object' to plot using the...
In pjnewcombe/Pmisc: A collection of miscellaneous functions.

Formats predictions into a ROCR ‘object’ to plot using the RocPlots function.

1	FormatRocrObjects(predictions.list, true.outcomes, fpr.stop = 1)

`predictions.list`	A named list of predictions for each different analysis/model, for each person/variable, and for each fold/replicate. First level is the analysis/model names. Second level can be matrices (rows people/vars, cols folds/replicates) or a list where each element corresponds to a different fold/replicate, and contains a vector of predictions across people/replicates.
`true.outcomes`	The true outcomes of disease/variable causality. Can be a matrix (rows people/vars, cols folds/replicates) or a list where each element corresponds to a different fold/replicate, and contains a vector of truth indicators. NOTE: These are assumed to be the same across analyses.
`fpr.stop`	Maximum x to go up to on the x-axis for a partial ROC