Add a new language [Valencian as a dialect of Catalan]

  Hi,

  I need help to decide what needs to be added to docutils so that Valencian 
language be admitted as a language. As a note, I would like to state that we 
reuse Catalan as much as possible:

  - The 'ca' translations in docutils too - no need to touch them
  - The language code used for the generated web pages is 'ca-va'
  - The language code for the translations is 'ca@valencia'
  - locale used in my system is 'ca_ES.UTF-8@valencia':
    [ ] ca_AD ISO-8859-15
    [ ] ca_AD.UTF-8 UTF-8
    [*] ca_ES ISO-8859-1
    [*] ca_ES.UTF-8 UTF-8
    [*] ca_ES.UTF-8@valencia UTF-8
    [*] ca_ES@euro ISO-8859-15
    [*] ca_ES@valencia ISO-8859-15
    [*] ca_ES@valencia UTF-8
    [ ] ca_FR ISO-8859-15
    [ ] ca_FR.UTF-8 UTF-8
    [ ] ca_IT ISO-8859-15
    [ ] ca_IT.UTF-8 UTF-8

  * Valencian is a dialect of Catalan:
    - https://en.wikipedia.org/wiki/Valencian_language
    - https://en.wikipedia.org/wiki/Catalan_Countries

## IANA registry
# http://www.iana.org/assignments/language-subtag-registry/language-subtag-registry

Type: language
Subtag: ca
Description: Catalan
Description: Valencian
Added: 2005-10-16
Suppress-Script: Latn

Type: variant
Subtag: valencia
Description: Valencian
Added: 2007-03-06
Prefix: ca
Comments: Variety spoken in the "Comunidad Valenciana" region of Spain,
  where it is co-official with Spanish.
--

## ISO 639-2
# https://www.loc.gov/standards/iso639-2/php/English_list.php

Catalan    Catalan; Valencian  catalan; valencien  cat  ca
Valencian  Catalan; Valencian  catalan; valencien  cat  ca
--

  The reason is to be able to generate content with Sphinx.

  With all this, how do you see it?

  Regards
  Toni
-- 
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