Do not create a Graphviz file

Just write a new edgelist. The Graphviz file can be created afterwards
with `edgelist_to_Graphviz.py`.

Overlap/Analysis/extract_component_nx.py

@@ -10,7 +10,6 @@ given as argument of the script.
 """
 
 import networkx as nx
-from networkx import nx_agraph
 
 import report_graph
 
@@ -54,7 +53,4 @@ if __name__ == "__main__":
     len_H = len(H)
     print("Number of nodes:", len_H)
     print("Number of edges:", H.number_of_edges())
-    A = nx_agraph.to_agraph(H)
-    report_graph.partition_graph_date(A, H.graph["e_overestim"])
-    A.write("eddy_graph.gv")
-    print('Created file "eddy_graph.gv".')
+    nx.write_edgelist(H, "component.csv", data = False)