This is a massive rewrite of the help text and cli.rst section of the
manual. All command-line flags now have their own help and are
specifically index. qpdf --help is completely redone.
QPDFObjectHandle gets copied a lot, so let's not add another field.
For performance reasons, QPDFObjectHandle does not indirect through a
smart pointer, so this would also be an ABI change.
At one time, it seems that I was starting to use the <firstterm>
feature of docbook, but I forgot about it long ago, and there is
nothing consistent. In the absence of an actual glossary, just use
emphasis for terminology and don't tag it in any special way. This
could be fixed later if we wanted to.
:option: is stronger and assumes a reference to a list of options.
Since we don't have that yet, just use :samp: for options. Inside
literal code blocks, there is no expansion, so just remove markup.
Also remove linearization from qpdf-manual.pdf. It's a small file, and
removing the dependency on the qpdf executable significantly shortens
build times.
We were using SGML entities for various non-ASCII characters so they
could convert properly for both HTML and print, but this is no longer
necessary as we move from docbook to RST, so just replace them. Note
that the conversions done by sphinx automatically handle "smart
quotes", so it works to just use regular quotes in place of &LDQUO;
and &RDQUO;.
With docbook, this was not converted properly in the PDF version, but
since we are moving out of docbook, we can just put the Unicode
character in the source.
The impact on the code would be extremely high, and using it would
clutter the code greatly because it would break chaining like
a.getKey("/B").getKey("/C"). There are better ways to deal with the
issue.