build from nipy/heudiconv, removed defunct heuristic
minor update:
- build from nipy/heudiconv instead of isolovey branch (since fix for MAX_CSA exists)
- removed defunct heuristic for addiction study
known issues:
- overriding heuristic with a file that has the same name as built-in heuristic doesn't seem to work (uses built-in version, but copies the external one to the heudiconv folder)