Introduced a new resource compiler script kiwix-compile-i18n that
processes i18n string data stored in JSON files and generates sorted C++
tables of string keys and values for all languages.
* Switch to debhelper compat 13
* Increase test timeout via `meson test`
* Depend on same version of libzim as meson.build specifies
* Restore mistakenly deleted libkiwix-dev.manpages
* We still need this file to instruct Debian to associate it with the
libkiwix-dev package.