feat(plugin): add spinner dialog plugin
feat(plugin): add spinner dialog plugin

https://github.com/driftyco/ionic-native/issues/69

xueron/ionic-native,xueron/ionic-native,xueron/ionic-native,ramonornela/ionic-native,klirix/ionic-native,ramonornela/ionic-native,klirix/ionic-native,xueron/ionic-native,ramonornela/ionic-native,driftyco/ionic-native,driftyco/ionic-native,ramonornela/ionic-native,driftyco/ionic-native,klirix/ionic-native