Log Message:
po4a: update to 0.52

0.52:

Core:
 * po4a-translate complains if the input po file is outdated
 * teach po4a-updatepo about the --porefs options that was already documented.
 * rename --porefs values after msgmerge option's name: noline->file
   and none->never. Both variantes are accepted; the later is documented.

po4a:
 * New option --no-update to not touch the po files.

AsciiDoc:
 * Properly deal with item text missing its leading indent
 * Allow empty attribute lists, by bexelbie

Text:
 * Add an option to treat Key/Value pairs as verbatim

RubyDoc:
 * New module by Francesco Poli

Wml:
 * Make title translatable, by yangfl

Documentation:
 * Various fixups by Alexander Golubev.

Translations:
 * Setup WebLate to ease the life of translators.
 * Update Brazilian Portuguese, thanks to Luiz Fernando Ranghetti.
 * Update Czech, thanks to Michal Čihař.
 * Update Dutch, thanks to Frans Spiesschaert
 * Update German, thanks to Helge Kreutzmann
 * Update Italian, thanks to Marco Ciampa.
 * Update French, thanks to Alban Vidal and to Jean-Baptiste on Weblate.
 * New translation: Norwegian Bokmål, thanks to Petter Reinholdtsen.
 * Update Russian, thanks to Alexander Golubev and to Igor on Weblate.
 * Update Ukrainian, thanks to Yuri Chornoivan.