The push back buffer has to be increased

[friesey]

Some large files create problems, some of them could be solved. There is at least one left that does not crashes the program but throws an error message like this:

"org.apache.pdfbox.exceptions.WrappedIOException: Could not push back 123575 bytes in order to reparse stream. Try increasing push back buffer using system property org.apache.pdfbox.baseParser.pushBackSize54" + file path of the file that causes this error.

[friesey]

So far, I test if a PDF is bigger than 16 MB. If yes, examination is skipped and a message is displayed.