One click or auto- update UA definition strings

[gofar12]

This helps to keep up with continuous updates of browsers, and saves much time. Top 5 most popular browsers is enough. Modern popular browsers all update automatically. Deprecate browser versions older than 5 years or hide them with an easy button/check to keep UA list clean..

It would be great also to show how popular the browsers (UA) are on the Internet and how popular they are amongst UserAgent-Switcher users.

[mylovepu]

[mylovepu]

[ray-lothian]

If you are willing to keep the JSON file updated, I'll implement the github auto updating feature