OpenSystemsDevelopment / qpdf

Otherwise we get errors if we added a class.

If /AP is a dictionary of streams rather than a dictionary of
dictionaries, disregard /AS, which is supposed to point to a subkey of
one of the dictionaries. This fix prevents qpdf's annotation
flattening from discarding some annotations when /AS is erroneously
set.

'#' was omitted from the list of chars that need to be escaped.

Warn if catalog type entry is invalid (fixes #810)

Improve --optimize-images to find images nested within XObjects

Code tidy QdfFixer methods

The sample file (nested-images.pdf) includes a pdf with an image that is
nested within an XObject within an XObject in the Resources dict of the
only page. These images were ignored in prior versions of qpdf.

Change type of local var lines to string_view. Also, instead of
constructing a list of lines, read the entire input into a single string
and break it up into lines on the fly.stash

...where the first "number" is an indirect object that happens to be a
number.

Exclude uninitialized, destroyed and reserved objects.