Improve Privacy Policy to explain Google Play Data Sharing

Caused a user feedback request:

> I’ve noticed that the Anki app on Android states, “may share and collect these data types with third parties (personal info, app activity, audio, photos and videos, files and docs).” Could you clarify how data sharing works on Android? Specifically, who is the data shared with, and are there options to opt out of sharing or delete my information? I love your app, but I need more clarity on this issue, and I couldn’t find any answers on GitHub.

https://forums.ankiweb.net/t/anki-android-data-policy/61891/

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Current Policy: https://github.com/ankidroid/Anki-Android/wiki/Privacy-Policy