release 1.2.0
release 1.2.0

737cd3e Update Readme for 1.2.0
59342fe android: fix recordPermission for android 6
3927e91 android: add record permission at runtime
953f83e ios: add audio notification and fix audio routing.
82a3e70 ios: add debug application state function
7d6b6b6 ios: use AVAudioSessionCategoryPlayback to support play in background
387bd17 index.js: use ES6 class singleton
404ebcc ios: add record permission promise api
bcba6b5 ios: fix xcode warnning for unused variable.
6f6f797 ios: fix warnning of unexpected optionality of parameters
e1a6551 ios: catch all exceptions for functions which throws
87973ee ios: fix audio route changed by webrtc when answered and related issue.
5b9db5e ios: add debug function to investigate properties ofaudio session
8d9fd15 ios: normalize log messages
62685e0 [ios] use NSLog instead print for log integrate

zxcpoiu/react-native-incall-manager,zxcpoiu/react-native-incall-manager,zxcpoiu/react-native-incall-manager