Add real-time multi-echo fMRI dataset to documentation

[tsalo]

Summary

Now that @jsheunis has released his super-cool real-time multi-echo dataset on Dataverse, we should add it to our list of public multi-echo datasets here!

Additional Detail

None

Next Steps

1. Add name of dataset with link to resources.rst.
2. Maybe reorganize the list of datasets into a table?

[jbteves]

So I'd like to wait on this until we resolve a bug where dataverse doesn't actually let you download the whole dataset.

[jsheunis]

Good point @jbteves. I'll post updates on the issue here.

[tsalo]

The bug might still exist, but there are detailed access instructions on the Dataverse page that can be followed, so I think we can add the dataset to our documentation.

[jbteves]

That seems fair. I'm fine with adding it. I've been playing around with it and it's pretty neat/useful!