Unrecognized tags raises a MismatchedTag error

[Delgan]

According to the README:

# Unrecognized tags are left as-is.
parse("<b><element1></element1></b>")

On my computer, this raises a MismatchedTag error anyway.

>>> parse("<element1></element1>")
OK
>>> parse("<b></b><element1></element1>")
OK
>>> parse("<b></b><element1></element1><b></b>")
NOK
>>> parse("<b>element1></element1></b>")
NOK
>>> parse("</element1>")
OK
>>> parse("<b></b></element1>")
OK
>>> parse("<b></element1>")
NOK

I guess all of these examples should be OK.