h5bp/html5-boilerplate — pull request #1268 by aalexgabi (2012-11-27 13:00:00+00:00)
Title: Changed html meta charset tag to uppercase UTF-8

According to http://www.w3schools.com/html5/att_meta_charset.asp the list of values accepted by charset attribute of the meta tag is here http://www.iana.org/assignments/character-sets.

This list does not include lowercase utf-8.