Admob 19.3.0

• Single ANE with 32 and 64 bits
• Updated Admob to the latest version 19.3.0

Rewarded Ads and Admob 16.0.0

• Added support for rewarded video
• Admob dependency: com.google.android.gms:play-services-ads:16.0.0

New version using AndroidStudio and Gradle

• AAR project with Android Studio and Gradle configurations
• Refactored packages
• AdMobManager inside the class ExtensionContext transformed to a singleton to fix bug (NullPointException acessing _adMobMan)