OpenSystemsDevelopment / qpdf

Run this:

for i in  **/*.cc **/*.c **/*.h **/*.hh; do
  clang-format < $i >| $i.new && mv $i.new $i
done

This makes it much more convention to use the initializeFromArgv
functions since you can use string literals.

This was used, but it no longer is, so let's not keep the extra
complexity around.

Handle optional choices in addition to required choices. Refactor the
way help options are added to completion to make it work with optional
help choices.