remove `rnpm` instructions from README (#1130)
remove `rnpm` instructions from README (#1130)

* remove `rnpm` instructions from README

* docs: remove extra
oblador/react-native-vector-icons,oblador/react-native-vector-icons,oblador/react-native-vector-icons,oblador/react-native-vector-icons,oblador/react-native-vector-icons