brew install automake
brew install libtool

brew tap homebrew/versions
brew install homebrew/versions/protobuf
brew install homebrew/versions/protobuf260
ln -s /usr/local/Cellar/protobuf260/2.6.0/bin/protoc /usr/local/bin

git clone https://github.com/alexeyxo/protobuf-objc.git
cd protobuf-objc
./scripts/build.sh

protoc --plugin=/usr/local/bin/protoc-gen-objc person.proto --objc_out="./"