Based upon some ideas done by Aslak in http://declarch.pastebin.com/m4c2d1955

Create an SPI abstraction for generic resources (called "Artifact" in the linked pastebin).

public interface Artifact()
{
InputStream getStream();
}

We may then create some concrete implementations in impl-base:

URLArtifact
FileArtifact
ClassLoaderArtifact

Alongside this task we need some simple unit tests.

When done we can open an issue to integrate with ArchiveBase