CocoaPods 清理并重新安装依赖

碰到了 CocoaPods 挂掉，怎么 install 也不成功的情况，不要惊慌，可以按下面的步骤彻底重置项目的 CocoaPods

rm -rf ~/Library/Caches/CocoaPods; 
rm -rf Pods; 
rm -rf ~/Library/Developer/Xcode/DerivedData/*; 
pod deintegrate; 
pod setup; 
pod install;