RucursionError -> RuntimeError for Python3.4

Author: shtaxxx

veriloggen/dataflow/dataflow.py

@@ -48,7 +48,7 @@ def implement(self, m, clock, reset, seq_name='seq', aswire=False):
 
         try:
             dataflow_nodes = copy.deepcopy(self.nodes)
-        except RecursionError:
+        except RuntimeError:
             dataflow_nodes = self.nodes
             limit = sys.getrecursionlimit()
             print("Warning: Current dataflow definitions are not copied.", file=sys.stderr)