Add translations to mandatory fields XLSX file

[spwoodcock]

Is your feature request related to a problem? Please describe.

• The mandatory fields XLSX file is used to store useful fields for field data collection.
• This form is merged with a user provided form including the actual survey questions.
• However we do not currently have translations for these questions, only an English version.

Describe the solution you'd like

• We need to add translations for most common languages so that we can merge these with forms where users have included translations.
• The list of all available language codes is ridiculously large: https://www.iana.org/assignments/language-subtag-registry/language-subtag-registry
• We should filter down the most useful (initially keep this simple, but then expand out later on):
  • French
  • Spanish
  • Italian
  • Swahili
  • Nepali
  • Hindi
  • Tamil
  • Bengali
  • Chinese simplified (mainland China)
  • Chinese traditional (other)
• If translation fields are included in the user uploaded form, we should match and include the translated columns for the mandatory fields too.

[spwoodcock]

I updated to include Swahili, French, Spanish translations. The others are still pending / some thought for how to solve this.