import in __init__.py no longer prevents setup.py from working

overviewer_core/__init__.py

@@ -1,5 +1,7 @@
 # c_overviewer must be imported first, because it imports other
 # modules; leaving this out can lead to bad dependency loops
 
-import c_overviewer
-
+try:
+    import c_overviewer
+except ImportError:
+    pass