Better release build reporting

The ResearchLogger reports whether a build is a release build or not
to avoid polluting data with IME debugging work by developers.
Previously this was done by checking a constant flag, which was also
serving the dual purpose of masking out debug code in release builds.

This change introduces a heuristic to determine whether a build was
created by a developer (using the package versionName), and annotating
the data sent to the server appropriately.

Change-Id: Icbad17c66b703cabf6d23d05e2c7c41bcceaae45