Replace frontend string with const
WIP support for theme hinting when getting locale translator
Additional support for locale + store specific purge
Merge branch 'feature/theme-purging' into develop

* feature/theme-purging:
  Additional support for locale + store specific purge
  WIP support for theme hinting when getting locale translator
Merge branch 'develop'

* develop:
  Additional support for locale + store specific purge
  WIP support for theme hinting when getting locale translator
  Replace frontend string with const