This better describes what it does.
Also, took this opportunity to update a bunch of the uifield code
(no multi line variable declarations, prefix state variables with _,
eliminate unnecessray lodash, etc)
Fixes issue with nested/namespaced fields, such as `maxspeed/advisory`,
in situations where would try to use a css selector or element id.
Can't use characters like '/' in a css selector.
* 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)
