Merge pull request #1688 from apollographql/flow

add initial flow typings for apollo-client

.flowconfig

@@ -0,0 +1,9 @@
+[ignore]
+
+[include]
+
+[libs]
+./index.js.flow
+
+[options]
+suppress_comment= \\(.\\|\n\\)*\\$ExpectError

.travis.yml

@@ -10,6 +10,9 @@ install:
 script:
   - npm test
 
+    # test flow types (validity and use cases)
+  - npm run flow-check
+
     # run coverage and file size checks
   - npm run coverage
   - coveralls < ./coverage/lcov.info || true # ignore coveralls error

CHANGELOG.md

@@ -4,6 +4,7 @@
 - Make ApolloClient.resetStore() and QueryManager.resetStore() return a promise instead of void [PR #1674](https://github.com/apollographql/apollo-client/pull/1674)
 - Fix bug that caused errors in `writeToStore` to be rethrown as uncaught errors [PR #1673](https://github.com/apollographql/apollo-client/pull/1673)
 - Feature: Pass a function to `optimisticResponse` and it will be called with the `variables` passed to the mutation [PR #1720](https://github.com/apollographql/apollo-client/pull/1720)
+- Feature: Added support flow flow typechecking [PR #1688](https://github.com/apollographql/apollo-client/pull/1688)
 
 ### 1.2.2
 - Fix: Remove race condition in queryListenerFromObserver [PR #1670](https://github.com/apollographql/apollo-client/pull/1670)