fix readme.md
fix readme.md

BenBBear/cordova-plugin-leanpush,easychen/cordova-plugin-leanpush,BenBBear/cordova-plugin-leanpush,xfstudio/cordova-plugin-leanpush,easychen/cordova-plugin-leanpush,xfstudio/cordova-plugin-leanpush,xfstudio/cordova-plugin-leanpush,easychen/cordova-plugin-leanpush