chore: adding information to main readme about user interaction plugin (

#767)

README.md

@@ -141,6 +141,7 @@ OpenTelemetry can collect tracing data automatically using plugins. Vendors/User
 #### Web Plugins
 - [@opentelemetry/plugin-document-load][otel-plugin-document-load]
 - [@opentelemetry/plugin-xml-http-request][otel-plugin-xml-http-request]
+- [@opentelemetry/plugin-user-interaction][otel-plugin-user-interaction]
 
 To request automatic tracing support for a module not on this list, please [file an issue](https://github.com/open-telemetry/opentelemetry-js/issues). Alternatively, you can [write a plugin yourself](https://github.com/open-telemetry/opentelemetry-js/blob/master/doc/plugin-guide.md).
 
@@ -191,6 +192,7 @@ Apache 2.0 - See [LICENSE][license-url] for more information.
 [otel-plugin-pg-pool]: https://github.com/open-telemetry/opentelemetry-js/tree/master/packages/opentelemetry-plugin-postgres/opentelemetry-plugin-pg-pool
 [otel-plugin-pg]: https://github.com/open-telemetry/opentelemetry-js/tree/master/packages/opentelemetry-plugin-postgres/opentelemetry-plugin-pg
 [otel-plugin-redis]: https://github.com/open-telemetry/opentelemetry-js/tree/master/packages/opentelemetry-plugin-redis
+[otel-plugin-user-interaction]: https://github.com/open-telemetry/opentelemetry-js/tree/master/packages/opentelemetry-plugin-user-interaction
 [otel-plugin-xml-http-request]: https://github.com/open-telemetry/opentelemetry-js/tree/master/packages/opentelemetry-plugin-xml-http-request
 [otel-shim-opentracing]: https://github.com/open-telemetry/opentelemetry-js/tree/master/packages/opentelemetry-shim-opentracing
 [otel-tracing]: https://github.com/open-telemetry/opentelemetry-js/tree/master/packages/opentelemetry-tracing