* Update output file format for i18n_check tool
* Update i18n engine to work with new format
* Update tests
* Fix UI bootstrap test
* Update loader tests and fix getTranslationsByLocale function
* Fix messages passing to IntlProvider
* Update messages interface
* Resolve comments
* Resolve comment
I was surprised when I tried to spread a `Set` in TypeScript and the browser complained about `Set.slice()` not being defined. This is because TypeScript does not automatically enable support for iterators when targeting earlier ES versions, like we do in the browser, unless you use the `"downlevelIteration": true` compiler option. This injects some helpers into the necessary files for reading/spreading iterators, which can be stuffed behind an import statement with using the `"importHelpers": true` compiler option and include `tslib` in our dependencies. This is already a dependency of several of our packages, so it shouldn't cause any additional modules.
* Add Guideline for i18n engine
* Update Guideline according to changes in i18n engine.
* Update examples in Guideline
* typo
* improve i18n guideline: add table for better view, use single quotes for js strings, fix description for testing, use uniq "message id" name
* fix readme description for guideline
Co-authored-by: maryia-lapata "mary.lopato@gmail.com"
* set kibana locale in kibana.yml config
* remove accept-language-parser
* remove unnecessary tests
* fix readme description, fix description for locale in kibana.yml
* add point, that i18n.locale option should have exact match
* update kbn/i18n README
* Update README.md
* use getUiTranslations in render_mixin, remove i18n_mixin
* move registering translation files to mixin function
* Add unit-tests for i18n engine
* tests for angular wrappers under i18n engine
* split to packages in accordance to specific library
* split to packages depending on tech and environment
* make env modules names consistent
* remove intl polyfilling
* move laoder to root, i18n folder to core
* Add unit-tests for i18n engine
* tests for angular wrappers under i18n engine
* rebase on split package, injectIntl component
* eslint fixes
* use method names for checking, test i18n-values in directive
* use real html content while testing directive
* add test for angular directive without values
* split to packages in accordance to specific library
* split to packages depending on tech and environment
* make env modules names consistent
* remove intl polyfilling
* move laoder to root, i18n folder to core
