gitignore update for Xcode project
gitignore update for Xcode project

jCho23/MobileAzureDevDays,kpiteira/MobileAzureDevDays,jCho23/MobileAzureDevDays,kpiteira/MobileAzureDevDays,kpiteira/MobileAzureDevDays,jCho23/MobileAzureDevDays,jCho23/MobileAzureDevDays,kpiteira/MobileAzureDevDays,jCho23/MobileAzureDevDays,kpiteira/MobileAzureDevDays,kpiteira/MobileAzureDevDays,jCho23/MobileAzureDevDays