* Add Firestore_IntegrationTests_macOS to Xcode
* Change deployment target from 10.14 to 10.10
* Make standard target edits
* Force C99/C++11
* Use shared test info.plist
* Remove CODE_SIGN_IDENTITY
* Add Firestore_IntegrationTests_macOS to the Podfile
* Have sync_project handle macOS integration tests
* Pod install and sync_project
* Add header search paths and ldflags
* Build integration tests on macos
* Remove integration tests from unit tests
* Make Firestore_IntegrationTests_macOS buildable from the command-line
* Rename Firestore/Example/App/macOS_example to macOS
* Update paths to macOS and names to Firestore_Example_macOS
* Add Firestore_Tests_macOS target
This uses a shared Tests Info.plist. This is important because it
configures NSPrincipalClass
* Teach sync_project about Firestore_Tests_macOS
* Add files to Firestore_Tests_macOS
* Add Firestore_Tests_macOS target to the Podfile
* Add HEADER_SEARCH_PATHS to match iOS
* Force C99/C++11 conformance
* pod install after adding Firestore_Tests_macOS
* Get macOS tests to link
* Add spec test json files to the macOS tests
* Remove development code signing
* Disable app sandboxing to allow GoogleTest death tests to succeed.
* Add a project sync script
* Give an error if the configuration references a group that doesn't exist
* Fix hard_assert_test reference
* Run sync_project to sort all project elements