High level C++ bindings for JNI calls

As discussed on Reddit, here is an improvement idea.

Either adopt one of the following C++ JNI libraries:

- [cppJNI](https://github.com/nokia/cppJNI)
- [JavaCPP](https://github.com/bytedeco/javacpp)
- [jni.hpp](https://github.com/mapbox/jni.hpp)

Or having a Google provided one that takes advantage of templates and compile time programming to wrap JNI calls into C++ type safe calls, without the low level strings, similar to the approaches taken by the libraries above.

Start by reviewing the issue's proposed libraries—cppJNI, JavaCPP, and jni.hpp—and the existing Android NDK JNI integration. The issue names no repository files, entry points, or tests, so the scope would first require deciding between adopting a library and designing a Google-provided type-safe wrapper. Done would require an agreed approach and implementation plan.

Written by the indexing model from the issue text.