Import Shared Artefacts

	public static class CustomArtefacts {
		public String mainJar; // Either a share _id, or a URL (admin only), or a string of the format ($infinite/share/get/{_id}; legacy) that points the JAR to use for the mapper/combiner/reducer classes
		public List<String> extraJars; // A list in the same format as "mainJar", used (eg) so that multiple jobs can share a common set of resources in JAR format
		public List<String> joinTables; // A list of _ids pointing to either sources or custom jobs - these are authenticated at publish-time so can be safely used by hadoop JARs (and are automatically available via _custom when the scriptingEngine is used)
		public Boolean selfJoin; // (OPTIONAL - defaults to false) If true, then in addition to whatever documents come from the "Input" elements, then current contents of this job's output is also processed 
	}