provide a mechanism for adding library JARs (test dependencies) to the deployment

The requirement to add extra JARs into the deployment is going to surface fairly early on in the adoption of Arquillian. In our examples, we are sticking to APIs in Java EE, but most projects have third-party JARs on which the application depends. Common examples are a logging framework, Apache Commons libraries, Google Collections, Hibernate Search...anything not available in the container.

We might need to update the @Deployment signature to support:
@Deployment
static Set<Archive<?>> x();

Or maybe a seperate @DeploymentDependencies (this could be defined in e.g. a super class)

@DeploymentDependencies
static Set<Archive<?>> x()

We are also going to need to consider providing APIs for resolving Maven dependencies (groupId, artifactId, version) or resolving test dependencies from the Maven pom. We need to be flexible.