Bumped version to 7.1.0 (firebase#476)

Bumped version to 7.0.0 (firebase#451)

Bumped version to 6.5.1 (firebase#446)

Bumped version to 6.5.0 (firebase#439)

Bumped version to 6.4.0 (firebase#419)

Bumped version to 6.3.0 (firebase#399)

* Bumped version to 6.3.0

* Updated changelog

Bumped version to 6.2.0 (firebase#392)

bump version to 6.1.0 (firebase#375)

* bump version to 6.1.0

* update changelog to include firestore version bump

Bumped version to 6.0.0 (firebase#333)