docs: Mention that Webcam requires https (or localhost).

website/src/docs/webcam.md

@@ -7,6 +7,8 @@ permalink: docs/webcam/
 
 The Webcam plugin lets you take photos and record videos with a built-in camera on desktop and mobile devices.
 
+> To use the Webcam plugin in Chrome, [your site should be served over https](https://developers.google.com/web/updates/2015/10/chrome-47-webrtc#public_service_announcements). This restriction does not apply on `localhost`, so you don't have to jump through many hoops during development.
+
 [Try live!](/examples/dashboard/)
 
 ## Options