Adds an Android performance test This commit introduces a new performance test for Android builds. Unlike traditional performance tests, the "templates" of Android builds are real, external, projects checked out from Git. They are tweaked to allow exeuction on the latest (development) version of Gradle, and add the traditional measurements (CPU, heap).
Adding an Android performance test requires extending the `AbstractAndroidPerformanceTest` class, which itself is a cross-version performance test.
This first step adds a single "medium" Android build as an experiment. It's worth noting that the performance test will only execute if:
- the Android SDK is installed and path is set through the `ANDROID_HOME` environment variables - the `$ANDROID_HOME/licenses` directory contains the accepted license files