Detect Android emulator for Android setup

[joshdholtz]

Motivation

Fixes #89
Some Android emulators were not being detected by the RuntimePlatform.Android check

Description

• Some emulators (not all) are not detected by Application.platform == RuntimePlatform.Android
• Adds IsAndroidEmulator() function
  • Attempts to initialize an android.os.Build class to extract the FINGERPRINT
  • If FINGERPRINT is generic then it should be an Android emulator
  • Wrapped in try/catch because creating AndroidJavaClass will fail on iOS

⁉️ Additional thought... We could just get rid of the FINGERPRINT and rely on AndroidJavaClass because we don't care if its an emulator or not. We only care about it its an Android device 🤷‍♂️