Problems with single files make ami-ocr fail

[stefhk3]

See stracktrace below - might be better to skip these errors.

[main] ERROR org.contentmine.norma.util.CommandRunner - Process failed to terminate after :20
[Fatal Error] 👎-1: Premature end of file.
Exception in thread "main" java.lang.RuntimeException: nu.xom.ParsingException: Premature end of file.
at org.contentmine.eucl.xml.XMLUtil.parseXML(XMLUtil.java:392)
at org.contentmine.eucl.xml.XMLUtil.stripDTDAndParse(XMLUtil.java:1284)
at org.contentmine.image.ocr.HOCRReader.readHOCR(HOCRReader.java:205)
at org.contentmine.ami.tools.AMIOCRTool.createStructuredHtml(AMIOCRTool.java:171)
at org.contentmine.ami.tools.AMIOCRTool.processTree(AMIOCRTool.java:156)
at org.contentmine.ami.tools.AbstractAMITool.processTrees(AbstractAMITool.java:447)
at org.contentmine.ami.tools.AMIOCRTool.runSpecifics(AMIOCRTool.java:133)
at org.contentmine.ami.tools.AbstractAMITool.runCommands(AbstractAMITool.java:192)
at org.contentmine.ami.tools.AMIOCRTool.main(AMIOCRTool.java:116)
Caused by: nu.xom.ParsingException: Premature end of file.
at nu.xom.Builder.build(Unknown Source)
at nu.xom.Builder.build(Unknown Source)
at org.contentmine.eucl.xml.XMLUtil.parseXML(XMLUtil.java:389)
... 8 more
Caused by: org.xml.sax.SAXParseException; Premature end of file.
at org.apache.xerces.parsers.AbstractSAXParser.parse(Unknown Source)
... 11 more