Expand available languages in Jetpack app

Description

At the moment, Jetpack Android is limited to the "magnificent 16" languages for which Automattic pays for translations. This has garnered some negative reviews as outlined here: pxLjZ-7SD-p2. It also limits who can use the app and creates a confusing experience when migrating from the WordPress app (which supports more languages).

Proposed Solution

It'd be possible to expand the available languages by following Olivier's steps: pxLjZ-7SD-p2#comment-20028

• Add the missing locales to the GlotPress JP project on .com
• Adjust the constant in the Fastfile that tells which locales to download from the GlotPress project, to extend that list of downloaded locales to all of them.
• Be sure that all the Jetpack-specific strings in that GlotPress .com JP project are 100% translated in all the locales, to avoid falling into the issue I mentioned in my previous P2.
• Ideally, we’d probably also want to add some safety-net/check in the fastlane lane that downloads those Jetpack-specific strings into src/jetpack/res, so that it constantly checks that those JP-specific translations are 100% translated — even if we add a new original in the future.
• Remove the resourcesConfiguration limitation we intentionally put on the jetpack flavor in our build.gradle to Mag16

This would likely be a small project from a tech point of view, but might require some co-ordination with the i18n team around translations.

Start with fastlane/lanes/localization.rb and the resourcesConfiguration setting in WordPress/build.gradle, then inspect the Jetpack resources under src/jetpack/res. Coordinate with the i18n team to add locales and ensure Jetpack-specific strings are fully translated. Done means the expanded locale list downloads correctly, the Jetpack flavor is no longer limited to Mag16, and a safety check covers incomplete translations.