add accent color explanation in readme
add accent color explanation in readme

android lollipop and above
nieok/cordova-plugin-firebase,canado/cordova-plugin-firebase,Vying/cordova-plugin-firebase,arnesson/cordova-plugin-firebase,canado/cordova-plugin-firebase,ceisinger/cordova-plugin-firebase,DigitalsunrayMedia/cordova-plugin-firebase,arnesson/cordova-plugin-firebase,DigitalsunrayMedia/cordova-plugin-firebase,nieok/cordova-plugin-firebase,ceisinger/cordova-plugin-firebase,arnesson/cordova-plugin-firebase,Vying/cordova-plugin-firebase,tdachev/cordova-plugin-firebase,Vying/cordova-plugin-firebase,nieok/cordova-plugin-firebase,tdachev/cordova-plugin-firebase,DigitalsunrayMedia/cordova-plugin-firebase,ceisinger/cordova-plugin-firebase,canado/cordova-plugin-firebase,ceisinger/cordova-plugin-firebase,tdachev/cordova-plugin-firebase,krtek1979/cordova-plugin-firebase,krtek1979/cordova-plugin-firebase,arnesson/cordova-plugin-firebase