Better placement of translation files

[tooomm]

Description of Change
In the webclient, each language has their own folder with a single, identically named file, each containing the translated strings for a different language.
Instead, I would prefer to rename them to use speaking file names, have them all in one folder and therefore also reduce the file path level.
I see no reason why to have individual files with same names in separate folders.

Unless there is some limitation I'm not aware of...

Currently is: webclient/public/locales/<lang>/translation.json

∟ locales
   ∟ es
      ∟ translation.json
   ∟ fr
      ∟ translation.json
   ∟ nl
      ∟ translation.json
   ∟ pt_BR
      ∟ translation.json

Should be: webclient/public/locales/translation-<lang>.json

∟ locales
   ∟ translation-es.json
   ∟ translation-fr.json
   ∟ translation-nl.json
   ∟ translation-pt_BR.json

Changes needed:

• Webclient code linking the translations
• Current files with translated strings (names + placement)
• CI config for pulling translation updates (added paths)
• Config at Transifex (GitHub Integration)
  • To check:
    • Ressource setup at Transifex?
    • .tx/config file at GitHub