Scifio delegators

This branch, forked off the schema-2012-06 branch, adjusts the xsd-fu templates to create new delegator classes and new packages for the existing auto-generated ome-xml classes used in bio-formats and scifio (specifically those in the loci.formats.meta and loci.formats.ome packages).

These changes are a fundamental step towards migrating the loci.formats.* package contents to legacy code. To preserve backwards compatibility, classes in these packages must delegate to SCIFIO equivalents.

Thus, a new xsd_fu command ("xxxx_legacy") has been added for the six relevant classes:
OMEXMLMetadataImpl, MetadataStore, MetadataRetrieve, DummyMetadata, FilterMetadata, AggregateMetadata

Note that both the "_legacy" and non-"_legacy" targets produce classes with the same name, but different packages. The package on each non-"_legacy" output has been adjusted to ome.xml.meta.

To test this branch, run the "_legacy" and non-"_legacy" xsd-fu targets for each of the six classes, ensure that the packages are appropriate and that the delegator classes appropriately mirror the primary classes.