OpenSystemsDevelopment / qpdf

Fixes oss-fuzz case 394129398.

Issue arose from chaining multiple runlength filters and inflating a
compressed stream of ~100 bytes to several gigabytes.

There is no obvious fix without imposing an arbitrary implementation limit
and therefore potentially excluding valid PDF files.

This requires a special build option.

Check for direct outline items.

Fixes oss-fuzz case 	389339260.

Fixes oss-fuzz cases 376305073, 389974979 and 391974927.

When recovering XRef streams, start with the stream with the largest
/Size rather than the largest offset.

Also, if reconstruction fails to find a trailer with a valid /Root entry
search for a root object.

Change QPDFWriter stream_decode_level default to qpdf_dl_generalized (fixes #1286)

runtime error

Also, fix disabling of preserve_encryption to be ignore
stream_decode_level, but disable preserve_encryption if compress_streams is
false.

Fixes #1286

without filtering

Use NAMES keyword in find_library call

Fix QPDF::getAllPagesInternal warning

Fix QPDF::copyForeignObject warning

Provide correct obj_gen and offset.

Provide correct obj_gen.

This reverts commit ff2a78f579ebdd06b417e34260a17dba06e71137, reversing
changes made to 8f54319f7a6514110f4b05cbbf1cb1c9fc8cb6a0.

This reverts commit 0e92cf6bf399249c603c3d0212e898fd29e71fcd, reversing
changes made to 7d34b89a69e8e89c098dd373442f7df809c28eff.

This reverts commit c648b9a018105a3c30b3e7f3c5f8a058d3ddd92c, reversing
changes made to 12b67a3227df6b6df3a4f5f098e11cce173ff7d5.

This reverts commit 54cf0e519c49e3fb44c7ca1de95a1fffbafc211c, reversing
changes made to c648b9a018105a3c30b3e7f3c5f8a058d3ddd92c.

Also, make obj_cache private and rename to table.

Move methods responsible for loading or keeping track of objects to
QPDF_objects.cc.

Also, tidy pipeline constructors and make subclasses final where possible.