* Add header for API proposal
* Fix some bugs and add implmentation
* Fix header import
* Fix umbrella header
* Add ways to modify settings object
* Remove unnecessary nodoc
* Update with new API
* Add implementations for Firestore and RTDB
* Revert emulator settings class
* fix style
* Remove bad import and assertion on override
* Prevent database emu from being set after repo init
* Add unified emu to functions
* Add tests
* update header comment
* fix test failures
* remove unused variable
* fix database test
* cast NSInteger to long
* fix style
* Fix functions test in travis
* Remove valueForKeyPath in tests
* fix style
* update comments and remove explicit scheme
* save progress
* Implement reference validation for RTDB
* Add tests
* Add changelog entries
* Remove test logs
* Fix line lengths
* remove underlyingHost
* fix functions tests
* fix integration warnings in functions test
* fix functions test
* Fix infinite loop exposed in integration tests (#6912)
Co-authored-by: Paul Beusterien <paulbeusterien@google.com>
