as it silently strips non-numeric suffixes (e.g. a value of "123 foo" is transformed into a numeric value of 123 by `parseFloat`, which is typically not what we desire)
Include all preferred and fallback langauges in coreLocalizer.localeCodes even if higher-priority ones have 100% string coverage
Fallback to the user's preferred languages instead of directly to English when querying OSM wikibase documentation and Wikidata (re: #7996)
Add `lang` attribute to tag documentation text loaded from OSM wikibase or Wikidata (re: #7963)
Consolidate localization behavior and init to a coreLocalizer function and singleton
Explicitly support `en-US` locale
Rename coreData to coreFileFetcher and export a singleton rather than using a property of coreContext
Add `apiConnections` property of coreContext to simplify adding a source switcher
Replace some init functions with re-callable, promise-supporting `ensureLoaded` functions
Make coreContext itself load the UI if a container has been specified at init time
Fix code tests
* convert iD.Detect() iife to a module
* iD.Detect() should return loaded locale (except for 'en')
(The previous code was a hack to replace the detected locale with the loaded
locale. Now that Detect is a module, we can not replace the detected locale
from external code, but we can have Detect() return the locale we really want)
