(closes#3324)
Previously we allowed devs to swap out services that they didn't need.
This became difficult now that ES6 exports are immutable bindings.
But we can wrap the immutable bindings themselves in a live object,
to get back the flexibility that we used to have.
This change also drops the `taginfo` accessor on Context, since devs who want
to swap out taginfo service with something else can now do so through the live
binding. `iD.services.taginfo = myTaginfo()`
taginfo returns results that match anywhere within the string. So in Canada, you might get results like US:CA:SF. This change filters out such results.
Added a variation of the combo field for road networks. If the field’s value is blank or shares a prefix with the current country code, search taginfo for values beginning with the country code and a colon.
* 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)
