quick fix, setCfgMapping getattr check to hasattr

with getattr(cfg, k, None) unexpected behavior when value to map is equivalent to False (0, None, False, empty object)

netpyne/specs/netParams.py

@@ -846,5 +846,5 @@ def setNestedParam(self, paramLabel, paramVal):
     def setCfgMapping(self, cfg):
         if hasattr(self, 'mapping'):
             for k, v in self.mapping.items():
-                if getattr(cfg, k, None):
+                if hasattr(cfg, k):
                     self.setNestedParam(v, getattr(cfg, k))