XML element name parsing is not spec compliant

[lucacorti]

To add some more context on #128, we are using saxy to parse XML files generated by invoicing systems and we are seeing examples of this happening in the wild. e.g.:

<a>somevalue</a

>

This causes saxy to return an error because the end of element a is not detected. According to the XML spec though, whitespace is allowed between the element name and the closing > character, so I think this is a bug in the implementation.