Android sdk versions are outdated

[tdekoning]

The Android OS versions used in the build.gradle file of this project are very outdated.

This has the effect that this library cannot be used in certain conditions.

The gradle error is:

uses-sdk:minSdkVersion 16 cannot be smaller than version 21 declared in library [com.facebook.react:react-native:0.64.0] /Users/teddekoning/.gradle/caches/transforms-2/files-2.1/334b1b05ea5dadaf84bbec314981d992/jetified-react-native-0.64.0/AndroidManifest.xml as the library might be using APIs not available in 16
	Suggestion: use a compatible library with a minSdk of at most 16,
		or increase this project's minSdk version to at least 21,
		or use tools:overrideLibrary="com.facebook.react" to force usage (may lead to runtime failures)