feat: Added privacy policy (#22)

Author: Ark-kun

docs/privacy_policy.md

@@ -0,0 +1,28 @@
+---
+id: privacy_policy
+title: Privacy Policy
+---
+
+# Privacy Policy
+
+There are two main modes of using Tangle:
+* Deploying your own Tangle instance (e.g. running locally or creating your own HuggingFace Space)
+* Using a Tangle instance maintained by the Tangle team (such as the Tangle team's shared HuggingFace Space [https://huggingface.co/spaces/TangleML/tangle](https://huggingface.co/spaces/TangleML/tangle))
+
+The applicable privacy policy depends on which modes is used.
+
+## Your own Tangle instance
+
+When you install Tangle yourself, the Tangle team does not collect any personally-identifiable data from you (except the anonymized data currently collected by Google Analytics).
+In the future we might add deactivatable anonymized telemetry to track which app features are used.
+
+## Tangle instance maintained by the Tangle team
+
+Example of such Tangle instance is the Tangle team's shared HuggingFace Space [https://huggingface.co/spaces/TangleML/tangle](https://huggingface.co/spaces/TangleML/tangle)).
+
+When you interact (e.g. login, submit pipeline runs) with such Tangle instance maintained by the Tangle team,
+the data that you provide to the app (such as the HuggingFace authentication info, submitted pipelines) is received and stored by the Tangle instance.
+This is by design, since you're explicitly providing the data to the app to be processed and used by the app.
+To be able to function, the app needs to store and use the provided data.
+
+The data collected by the Tangle instances maintained by the Tangle team is covered by the following [Privacy Policy](https://www.shopify.com/legal/privacy).