Create an aar artifact for Android

The Android build system prunes unused resources, which would mean, if we could wrap these icons into an aar, the unused ones would be striped from the final apk. This would certainly make adding this icons much easier to any Android project.

Start by reviewing the repository's Android build configuration and current artifact packaging; the issue does not name files or tests. Define the AAR output so Android resource shrinking can remove unused icons, then verify that it can be added to an Android project and produces the intended artifact.

Written by the indexing model from the issue text.