Invalid closing tags should raise error

[adamfortuna]

Saw this one on here:

http://discuss.codeschool.com.s3.amazonaws.com/824c71d9d5867b65fee2dd5c596192164b2e97962d5.PNG

Looks like someone had this, and it wasn't marked as an error:

<h4>something<h/4>

This also seemed to happen here: http://i.imgur.com/00HeZ8x.jpg

<h3>Tour Dates</3>

[adamfortuna]

This one might not be an error -- http://cl.ly/image/3u2t2R291p1y Might need to be sure it's behaving as expected for this in multiple browsers though.

[nwronski]

The new parser output for these:

h3 is not a valid self closing tag
h4 is not a valid self closing tag