OpenSystemsDevelopment / qpdf

This is in preparation for implementing page groups.

Add a newline unconditionally before endstream even if a newline was
already written as part of the stream data.

Bad /W in an xref stream could cause a division by zero error. Now
this is handled as a special case.

Remove problematic test files

Rather than checking consistency of libqpdf.map, generate it.

The build now checks to make sure libqpdf.map has the right library
version number in it.

Also accept more errors than before.

Eliminate PCRE and find endobj not preceded by endstream. Be more lax
about placement of endstream and endobj.

Preparing to refactor some pattern searching code to use these instead
of their own memchr loops. This should simplify the code that replaces
PCRE.

Sometimes we want to ignore bad tokens rather than having them throw
an exception. A coverage case is commented out here and added in a
later commit.

Also fix a bug resulting from incorrect use of PointerHolder because
of this unused parameter.

Passed arguments to the constructor in the wrong order.

main() had gotten absurdly long. Split it into reasonable chunks. This
refactoring is in preparation for handling splitting output into
single pages.

This is added to contrib rather than examples because it requires
c++-11 and lacks a test suite, but it is still useful enough to
include with the distribution.

Required for strtol()