message: Add OSD 2022 link
  This changelist updates the Additional Resources section on the main page, adding a link for Open Source Days 2022.
diff: @@ -70,4 +70,4 @@ The following packages contain pre-built binaries for the latest release, includ
  - The [Developer Guide](http://www.materialx.org/docs/api/index.html) contains a developer-oriented overview of MaterialX with API documentation.
  - The [Python Scripts](python/Scripts) folder contains standalone examples of MaterialX Python code.
  - The [JavaScript](javascript) folder contains details on building JavaScript bindings for MaterialX.
  -- Presentations at the [Physically Based Shading Course](https://blog.selfshadow.com/publications/s2020-shading-course/#materialx) and [ASWF Open Source Days](http://www.materialx.org/assets/ASWF_OSD2021_MaterialX_slides_final.pdf) provide details on the roadmap for MaterialX development.
  +- Presentations at [ASWF Open Source Days](http://www.materialx.org/assets/ASWF_OSD2022_MaterialX_OSL_Final.pdf) and the [SIGGRAPH Physically Based Shading Course](https://blog.selfshadow.com/publications/s2020-shading-course/#materialx) provide details on the roadmap for MaterialX development.
  