Set language attribute in the html element

[pvdl]

Authors are encouraged to specify a lang attribute on the root html element, giving the document's language. This aids speech synthesis tools to determine what pronunciations to use, translation tools to determine what rules to use, and so forth.

Insert this attribute language="en" in the HTML element.

Further reading:
http://www.w3.org/International/tutorials/new-language-decl/qa-html-language-declarations
http://www.w3.org/html/wg/drafts/html/master/the-root-element.html#the-html-element

[alrra]

@pvdl see #1110.