Add viewport settings for mobile web

[tgolen]

<meta name="viewport" content="width=device-width, user-scalable=no, initial-scale=1">

[quinthar]

Can you elaborate on what this does and why it's MEDIUM?

[shawnborton]

I can add this one in to an existing PR quickly.

David - this basically just makes mobile web have the correct zoom level as well as the non-pinchable-zoom you would expect from any app on your phone. (meaning, you can't use your fingers to zoom in/out of an app)

[OSBotify]

🚀 Deployed to production by https://github.com/mountiny in version: 9.0.10-7 🚀

platform	result
🤖 android 🤖	success ✅
🖥 desktop 🖥	success ✅
🍎 iOS 🍎	failure ❌
🕸 web 🕸	success ✅

[OSBotify]

🚀 Deployed to production by https://github.com/francoisl in version: 9.0.11-5 🚀

platform	result
🤖 android 🤖	success ✅
🖥 desktop 🖥	success ✅
🍎 iOS 🍎	success ✅
🕸 web 🕸	success ✅