Updated to RN 0.57.1 and fixed iOS build process

[reime005]

• Update to RN 0.57.1
• Removed dummy.txt files from bundle step which were not available by default
• Specified exact react-native-camera commit to use in package.json

Should close #5

Build Tested with XCode 10.0

Running tested on Android Emulator API 28 x86 and Real iPhone 6s plus / iOS 12.0

[jgcmarins]

great job