Feature: Replace with Dummy Data

[nwittwer]

Reflex can be great for screenshots of production apps, and it would be cool to have the ability to define things like titles and descriptions, and easily replace elements on the page with those defined values. Sometimes there's customer-specific values that should not be captured, or you want to replace the content with translations, etc..

Idea: Use DOM selector matching or text value matching to auto-replace with defined values when certain URL loads.