add getSceneStyle v3 prop support, fixes aksonov#2033

bump version

fix: backTitle was not diplayed

fix: tintColor doesn't work for back/left button

4.0.0.beta.9 (aksonov#2025)

- Enhancement: support inheritance of scene props (useful for `headerMode` attribute for different RN StackNavigator animation)
- Fix: attempt to fix react-navigation pushes instead of jumping when user taps the same tab (aksonov#2024)
- Enhancement: use navBarButtonColor or tintColor or headerTintColor for image button tintcolor (aksonov#2028)
- Fix: use backBehavior='initialRoute' by default (aksonov#2026)
- Enhancement: allow right/leftTitle, right/leftButtonImage to be static functions within scene component
- Enhancement: allow wrapping all screens and navbar buttons with `wrapBy` parameter for `Router`. It could be `observer` from MobX, or `connect` from Redux or any other function.
- Fix: eslint formatting, fix CircleCI build

Merge pull request aksonov#2015 from aksonov/4.0.0-beta.8

PR for beta.8

Merge remote-tracking branch 'origin/master'

upgrade to RN0.44, bump version

Merge branch 'master' of https://github.com/aksonov/react-native-rout…

…er-flux

Add "chozun" production app (aksonov#1104)

Feature(multiple pop): now we can pop multipe scenes with Actions.pop (…

…aksonov#806)

* Feature(multiple pop): now we can pop multipe scenes with Actions.pop([number]), like Actions.pop(2)

* Fix(format)

* Fix(data check, format): compare data with index, add semicolon

* -Fix(format)

* Fix(format)