WebView + Native Android Examples

The examples are meant to be close to the minimal amount of code needed to get something running. The main goals are to show how to set up the build environment, use JNI and native rendering, and how to inject owr.js into a WebView.

The projects are set up to be used in Android Studio, but afaik you can also build them from the command line as well, using gradle.

To try one of the examples:
* Build OpenWebRTC with target 'android'
* Import the folder into Android Studio using "Import Project"
* Add ndk.dir=&lt;your-ndk-path-here&gt; to local.properties
* Run

The following directory structure is assumed:
```
.
├── openwebrtc
└── openwebrtc-examples
```
An alternative to using the above structure is to replace the links in `android/*/app/src/main/jniLibs/armeabi/`


If we're happy with the approach I'll add a README.md as well (cat $0 > README.md).