We would like to be able to distinguish between modules being run with different
executors by Hudson.

Many of our tests use a database, and they are able to reset it correctly. By
using the executor number, we hope to have one database schema per executor, and
thus be able to run a number of tests in parallel without the tests interfering
with each other.

Something as simple as setting the system property "hudson.executor.number"
would be sufficient for this.