Issue #2020361 by vijaycs85: Create LanguageConfigContext to activate configuration overrides based on language.

Issue #1620010 by dawehner, ParisLiakos, plach, jibran: Move LANGUAGE constants to the Language class.

Issue #1934964 by alexpott, Gábor Hojtsy, nevergone: Fixed Locale override subscriber should re-init context to clear caches.

Issue #1763640 by beejeebus, alexpott, YesCT, Jose Reyero, Gábor Hojtsy, das-peter, c31ck, heyrocker: Followup: Introduce config context to make original config and different overrides accessible.

Issue #1763640 by beejeebus, alexpott, Jose Reyero, c31ck, das-peter, YesCT, heyrocker, Gábor Hojtsy: Introduce config context to make original config and different overrides accessible.

Issue #1899994 by katbailey, plach, YesCT: Disentangle language initialization from path resolution.

Issue #1646580 by chx, Jose Reyero, beejeebus: Implement Config Events and Listeners, and storage realms for localized configuration.