wta: Support out-degree paramter for 'generate' command

Same rationale as for the `run` command

wta/bench.py

@@ -42,6 +42,9 @@ def check_zerotrans(args):
 def generate(args):
     check_zerotrans(args)
 
+    if args.out_degree:
+        args.edge_spec = ("transitions", str(int(args.out_degree)*int(args.states)))
+
     generator = args.generator
     states = args.states
     monoid = args.monoid
@@ -329,6 +332,7 @@ def main():
     gen_parser.add_argument('--symbols', required=True)
     gen_parser.add_argument('--zero-frequency')
     gen_parser.add_argument('--transitions')
+    gen_parser.add_argument('--out-degree')
     gen_parser.add_argument('--different-values')
     gen_parser.set_defaults(func=generate)