Deleting the super-legacy stuff

[MrPowers]

There are some references to super-legacy stuff in the README like spark-csv and spark-mongodb.

Let me know if you're open to deleting the old stuff and I can submit a PR, thanks!

[zero323]

Yeah, we should probably remove these and a few more. I am not sure what is the best approach here though.

When we discussed removals for the first time I imagined that we'll create another file (let's say REMOVED.md) and put things in there, with some standardized description of the removal reason. This would clearly indicate that the project was listed, but has been removed (and possibly indicate when it might be added back, i.e. if project is resurrected).

I'd also prefer to remove things one at the time ‒ it's easier to track things this way and keep any discussion focused.

[eliasah]

I agree with @zero323 . It would be better to keep track maybe in a separate file.

[zero323]

@eliasah Now we have one, it is just a matter of making a sweep, though there are some things that can go directly into trash bin I guess (like Berkley MOOCs, which are not even searchable on edx anymore).