Fix check for ios directory

Author: dionsake

bin/cocoapods.sh

@@ -3,7 +3,7 @@
 ## https://github.com/auth0/react-native-lock/blob/master/bin/cocoapods.sh
 
 ios_dir=`pwd`/ios
-if [ -d ios_dir ]
+if [ ! -d $ios_dir ]
   then
   exit 0
 fi
@@ -45,4 +45,4 @@ cd ..
 
 echo "Installing Pods"
 
-pod install --project-directory=ios
+pod install --project-directory=ios