Add Boolean Field mapping for Rally 2.0 Integration

Currently, there is no way to map Boolean fields in Rally to Predefined Choice fields in Aha. A Boolean field in Rally can only be mapped to a text field or a few other options like Aha Rank, and can only bring the data from Rally to Aha, not the other way.

We would like to see this work as a 2 way integration to be mapped with Predefined Choice fields.