- can't reliably use sinon.spy to tell whether a thing has been called,
so we listen for events instead and check server.requests()
- make sure to request the next page before dispatching `loadedImages` so
we can `server.respond()` to the request in the event handler if we want to
- also moves `localeDateString` in the openstreetcam service from parsing
code to display code, because it's very slow (we can just do this for the
images we look at, instead of all images we fetch)
Root cause was the `select` mode removing the "selected" class from all
elements upon `exit()`. Easy fix is to use a different class (here
"currentView") for street imagery elements.
(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()`
Bryan Housel