improvements to improve wrapper

[ymahlich]

new functionality:

• output of proteomics abundance data (imputed)
• ability to balance train/test/validate by auc for example
• conversion of mRECIST drug response metric in PDX datasets to auc
  • 'CR' -> 0.1
  • 'PR' -> 0.2
  • 'SD' -> 0.5
  • 'PD' -> 1.0