Does not handle Internal or External DTD Declaration #1
Description
Must prune !DOCTYPE element the following examples will not parse:
<?xml version="1.0"?>
<!DOCTYPE note [
<!ELEMENT note (to,from,heading,body)>
<!ELEMENT to (#PCDATA)>
<!ELEMENT from (#PCDATA)>
<!ELEMENT heading (#PCDATA)>
<!ELEMENT body (#PCDATA)>
]>(OR)
<?xml version="1.0"?>
<!DOCTYPE note SYSTEM "note.dtd">
...