Gumby maintenance (tutorial fixes, DAS6 support, custom trackers)

[devos50]

History: lots of fixes are done to this "simple" job scheduling scripting framework. See: #492 ToDo list for next available developer or student in our lab (8 weeks and 3 days estimate). This job is suitable for a junior developer, smart bsc student, student still doing their master degree.

• (2 days) install Gumby locally. Follow tutorials, identify errors. Submit the first Python "Hello World" job to the DAS5. Recommended to follow the basic tutorial.
• (1 week) re-visit all tutorials, identify mistakes, and add new tutorial Documentation improvements #501
• (1 day) Suggestion: remove for-loops from the scenario file scripts #499
• (2 weeks) Currently, Gumby supports conducting experiments on the DAS5 compute cluster, also see this tutorial. With the recent deployment of the DAS6, we should update Gumby and the documentation to support DAS6 experiments.
• (1 week) Use optionally a HTTP tracker inside Gumby for experiments. Recommended approach by @devos50 is to use a module approach like we have here: https://github.com/Tribler/gumby/blob/devel/gumby/modules/profile_module.py. (separate issue here Gumby should support a custom LibTorrent tracker #285)
• (1 week) Clean up post-processing scripts #498
• (2 weeks) Create Jenkins validation experiments for our experiments #502
• (1 week) Add support for Docker containerization #500

[synctext]

DAS6 support by @xoriole https://jenkins-ci.tribler.org/computer/DAS6_TUD/ 😲

[devos50]

@synctext Even though the head node is connected to Jenkins, the Gumby code (and libraries on the DAS6) is not compatible yet. I opened #503 to address this 👍

[pvanita]

I am working on this issue and successfully completed the first step, running the "Hello World"