Add stats slot for buildPredictor() output

[shraddhapai]

Must have routine getStats() function that prints various stats in predictor building. Includes:

• train/test breakdown overall
• train/test breakdown per resampling
• num nets/patients/query for resampling db
• num nets pass clique filtering
• edge distribution of nets

For this to work, turnkey predictor methods must save information with standardized names (e.g. resampling_savedDat.Rdata > phenoDF or TT_STATUS etc.,)