Update FSEP paper feature section 1 to clarify onboarding features

[NoraCodes]

Here, I've suggested two changes to the FSEP paper.

First, to clarify the distinction between "deny lists" and "deny list providers"; presumably, one provider could offer multiple lists, as observed in the many algorithmic combinations provided by oliphant.social.

Second, to add a feature for the MVP stage of implementation that allows administrators to better understand what they are opting into when they choose a particular list. This change is guided by my frustration with app stores, plugin directories, server browsers, and the like which lack robust hypertext tools and description fields and thereby ask users to make a decision with a very limited amount of information. Ideally, an admin could read, or at least glance at, all the policies of available deny lists and then choose the one that best suits the experience they're looking for.

I have signed the CLA.

[quintessence]

Thank you for these!

[quintessence]

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