Update build instructions to start with pub install
Update build instructions to start with pub install
dart-lang/protobuf,bwu-dart-contributing/dart-protoc-plugin,google/protobuf.dart,dart-lang/protobuf,dart-lang/dart-protobuf,taisph/dart-protoc-plugin,dart-lang/protobuf,taisph/dart-protoc-plugin,taisph/dart-protoc-plugin,dart-lang/dart-protobuf,dart-lang/dart-protobuf,google/protobuf.dart,google/protobuf.dart