Support resistance mutation in oncokb-annotator

[zhx828]

This is an effort to support resistance mutation based on the upcoming structure. We currently do assign resistance to mutation, but we are about to separate the resistance from oncogenicity. A mutation can be oncogenic and resistance at the same time.
To do list:

• Add column RESISTANCE_MUTATION, True, False in MAF/SV/CNA/Fusion annotations
• Update the logics in the clinical annotator to use resistance field returned through API to calculate the RESISTANCE_MUTATIONS and #RESISTANCE_MUTATIONS