[REMOVE] Silence

[dngray]

Checklist

• [X] I have read the guidelines in CONTRIBUTING.md
• [X] Include my name in CONTRIBUTORS.md
• [ ] I am affiliated with this alternative

Alternative name

Silence

Reason

Unmaintained last commit was in 2020 2 years ago https://github.com/SilenceIM/Silence/commits/master

If you're having to install an app like this, you might as well just install Signal instead and not leak metadata everywhere to your cell carrier.