Replace rust with rust2 entry in index.jade

[dermesser]

The library in rust.jade, https://github.com/GildedHonour/frank_jwt, is of horribly low quality:

• commit descriptions are lacking
• error handling is not present and panics on every error, i.e. not suitable for anything more than very basic prototyping
• library is very inflexible, e.g. relies on files to read keys from (instead of allowing arbitrary sources).

In contrast, the library in rust2.jade is of much higher quality (even on first sight), but hasn't been included yet. I urge you to accept this request, as including bad libraries like frank_jwt harms your (and everyone's) cause here.

[sebadoom]

Other Rust libraries have been added to the list, including the one you mentioned. Unfortunately we still don't have a clear admission process for libraries in the list. Once this is in place we will enforce certain quality requirements for libraries to remain in the list.

Tracked by #279 and #277.