fix(): FirebaseApp Class should not implement app.App (angular#2060)

While giving us a bit more type safety in development, implementing
app.App allows the Firebase JS SDK to break our builds in minor
releases. Which has bit us more than once.

I do not believe this is worth keeping around any longer.

Fixes angular#2059

chore(): Changelog for 5.1.1 and 5.1.2 (angular#2022)

Add StorageBucket injection token to storage docs (angular#1958)

5.1 release: support Firebase 5.5, multi-tab sync, function region se…

…lection, and Angular 7 (angular#1920)

* feat(afs): Support Firebase 5.5 and Firestore PersistenceSettings

* chore(): Now that app types are mostly fixed, pull from those

* chore(): Changelog entry for 5.1

* chore(): Use PersistenceSettings from interfaces, also fix types in firestore.ts

* fix(afs): Fix constructor ordering so this isn't a break

* feat(functions): Support region configuration via FunctionsRegionToken

* chore(): Changelog entry for region selection

* chore(): Support Angular 7 without peer dependency warnings

* chore(): Changelog for Angular 7

Bind messaging (angular#1889)

* fix(messaging): Fix for the binding issue and onTokenRefresh for Messaging

* chore(): 5.0.1 changelog and version bump

* chore(): 5.0.2 changelog

* docs(messaging): typo, closes angular#1888

chore(): angularfire2 shim (angular#1864)

chore(): release @angular/fire 5.0 🎉🔥🕺 (angular#1854)

chore(release): rc12 (angular#1838)

chore(): lean only on `firebase` types and compatibility with 5.0.4 (a…

…ngular#1729)

* chore(): lean only on `firebase` types and compatibility with 5.0.4

* chore(): rc.11 version bump and changelog entry

chore(): rc.10 (angular#1679)