Feature: Send language header

[nwittwer]

Problem: It's hard to test internationalization and see how a site will respond without using Google Translate or switching the device language. Instead, could we spoof the header language?

Related problem: Sometimes you don't have manual translations, but want to see how a design will look in another language using Google Translate.

• Accept-language
• Content-language

Resources
https://www.w3.org/International/questions/qa-lang-priorities
https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html

Tools
http://validator.w3.org/i18n-checker/