Add borgmatic (#279)

index.md

@@ -154,6 +154,7 @@ color by default via `NO_COLOR`.
 | [bfs](https://github.com/tavianator/bfs) | Breadth-first version of the UNIX find command | [2019-05-06 / 1.4.1](https://github.com/tavianator/bfs/releases/tag/1.4.1) |
 | [Bikeshed](https://github.com/tabatkins/bikeshed) | Spec/Document Processor | [2018-07-27 / 0.9](https://github.com/tabatkins/bikeshed/commit/04ea123d607a8d4bed692ad73dda1cb343bb5bbe) |
 | [Bloop](https://github.com/scalacenter/bloop) | Compilation/test server for Scala and Java | [2018-07-02 / 1.5.3](https://github.com/scalacenter/bloop/pull/555/commits/ff6f17a0155633f86440e10d7889f077e7fbc91c) |
+| [borgmatic](https://torsion.org/borgmatic) | Simple, configuration-driven backup software for servers and workstations | [2024-03-04 / 1.8.9](https://projects.torsion.org/borgmatic-collective/borgmatic/commit/16bc0de3fb76f027c81353899d4e7a4d6b386dbc) |
 | [buildkit](https://github.com/moby/buildkit) | Concurrent, cache-efficient, and Dockerfile-agnostic builder toolkit | [2022-07-20](https://github.com/moby/buildkit/commit/ebb1e827178a763f7f1150fc5a80a9b4f993d02f) |
 | [Bullseye](https://github.com/adamralph/bullseye) | .NET library for running a target dependency graph | [2021-01-01 / 3.6.0](https://github.com/adamralph/bullseye/blob/master/CHANGELOG.md#360) |
 | [c-ray](https://github.com/vkoskiv/c-ray) | The small C raytracer | [2021-09-24](https://github.com/vkoskiv/c-ray/commit/cd321107a650c68bfa62911f8baf691397e28898) |