Improve the current stewards list and find a better way to display who is taking on specific frameworks

[PatrickAlphaC]

Right now, I cannot tell which frameworks already have a steward. It would be great if we had a section to write this out so we know who to contact.

[mattaereal]

Have you taken a peek to https://frameworks.securityalliance.dev/contribute/contributors.html?

[PatrickAlphaC]

Maybe we can make that in the README/docs? It's still not clear to me who has ownership of what... For example, I did not know Coinspect was managing the wallet security, and I spent a large amount of time on that.

[mattaereal]

In the future we will use Github's project to avoid these kind of overlaps between top contributors and stewards

[PatrickAlphaC]

Fixes: #172

[mattaereal]

I have made public this: Security Frameworks

I will have to organize it. But there we'll coordinate assignments.