[GNNet challenge 2020] Update the code: datanetAPI bug

Dear participants, We have found a small bug in the API we provide to read the datasets (datanetAPI.py). This particularly affects the functions "get_maxAvgLambda()" and "get_global_delay()" of the API. If you are using RouteNet (https://github.com/knowledgedefinednetworking/RouteNet-challenge), please update the code with the latest version of the repository. You can do it with "git pull" from the terminal or downloading the code directly from the GitHub website. Alternatively, if you have already made major modifications to the code, you can replace only the file "datanetAPI.py" under the directory "RouteNet-challenge/code/". The same applies if you are using the API code provided at https://github.com/knowledgedefinednetworking/datanetAPI. Sorry for the inconvenience. Enjoy the challenge! And remember, if you have any questions/comments don't hesitate to use this mailing list to share them. Best Regards, Albert López Barcelona Neural Networking center Universitat Politècnica de Catalunya