search heuristic file path first (#434)

* search heuristic file path first

This allows heuristic modules names that conflict with existing module
names, such as using a heuristic module named "heudiconv.py"

Co-authored-by: Charles Samuels <[email protected]>
Co-authored-by: Yaroslav Halchenko <[email protected]>

Author: 3 people

heudiconv/utils.py

@@ -319,7 +319,7 @@ def load_heuristic(heuristic):
         path, fname = op.split(heuristic_file)
         try:
             old_syspath = sys.path[:]
-            sys.path.append(path)
+            sys.path.insert(0, path)
             mod = __import__(fname.split('.')[0])
             mod.filename = heuristic_file
         finally: