Outline proposed architecture based on requirements.

Author: felixarntz

README.md

@@ -14,5 +14,6 @@ For more information on the requirements and guiding principles, please review:
 
 * [Glossary](./docs/GLOSSARY.md)
 * [Requirements](./docs/REQUIREMENTS.md)
+* [Architecture](./docs/ARCHITECTURE.md)
 
 See the [contributing documentation](./CONTRIBUTING.md) for more information on how to get involved.