Log Message:
po4a: Update to 0.62

Changelog:
0.62
po4a tool:
 * Improve po_paths on misconfigurations, improve doc and error messages.

Asciidoc:
 * Unwrap all paragraphs by default (Github's #242).
   Introduce "forcewrap" option to re-enable line wrapping on output.
 * Support definition list continuations with indent (Github's #273)

DocBook:
 * Mark xreflabel attributes as translatable (GitHub's #267).

Documentation:
 * Fix some typos, thanks mestaritonttu.

Translations:
 * Updated: Croatian, thanks Milo Ivir.
 * Updated: Chinese (simplified), thanks taotieren.
 * Updated: Dutch, thanks Frans Spiesschaert.
 * Updated: French, thanks jmichault and Jean-Baptiste Holcroft.
 * Updated: German, thanks Helge Kreutzmann.
 * Updated: Hungarian, thanks Balázs Úr.
 * Updated: Italian, thanks Marco Ciampa.
 * Updated: Norwegian Bokmål, thanks Allan Nordhøy and Petter
   Reinholdtsen.
 * Updated: Portuguese, thanks Silvério Santos.
 * Updated: Portuguese (Brazil), thanks Rafael Fontenelle.
 * Updated: Russian, thanks Yuriy Balyuk and Artem.
 * Updated: Serbian (cyrillic), thanks Ivan Pesic.
 * Updated: Spanish, thanks Vladimir Támara Patiño and Emma Peel.
 * Updated: Ukrainian, thanks Yuri Chornoivan (українська).