Added SECURITY.md

[Jolah1]

Adds a SECURITY.md file as requested in #877

The file points to rust-lightning's existing SECURITY.md policy rather than duplicating it.

Closes #877

[ldk-reviews-bot]

I've assigned @tnull as a reviewer!
I'll wait for their review and will help manage the review process.
Once they submit their review, I'll check if a second reviewer would be helpful.

[tnull]

Thanks!

For future reference, and as noted on #877, it would generally be preferable to leave anything that is policy and/or security related to the core contributors/maintainers of a project. In this instance the diff is rather trivial, so fine this time.

[Jolah1]

Oh! I apologize.
This information is duly noted.
Thank you!

Thanks!

For future reference, and as noted on #877, it would generally be preferable to leave anything that is policy and/or security related to the core contributors/maintainers of a project. In this instance the diff is rather trivial, so fine this time.