doc: link to the jaeger plugin

License: MIT
Signed-off-by: Steven Allen <steven@stebalien.com>

docs/plugins.md

@@ -53,6 +53,7 @@ plugin type is likely the best interim solution.
 | [badgerds](https://github.com/ipfs/go-ipfs/tree/master/plugin/plugins/badgerds) | Datastore | x         | A high performance but experimental datastore. |
 | [flatfs](https://github.com/ipfs/go-ipfs/tree/master/plugin/plugins/flatfs)     | Datastore | x         | A stable filesystem-based datastore.           |
 | [levelds](https://github.com/ipfs/go-ipfs/tree/master/plugin/plugins/levelds)   | Datastore | x         | A stable, flexible datastore backend.          |
+| [jaeger](https://github.com/ipfs/go-jaeger-plugin)                              | Tracing   |           | An opentracing backend.                        |
 
 * **Preloaded** plugins are built into the go-ipfs binary and do not need to be
   installed separately. At the moment, all in-tree plugins are preloaded.