close #1 added IndexWriterFactory facade, hiding the writer
implementations from OSGi clients.
#2 migrated API to use OSGi Core R5 org.osgi.resource interfaces. api
and lib bundles export the package to simplify running the indexer on
older frameworks.
The flipside of the migration is that I had to remove Builder class
package from the API, as it depends on concrete implementations
Requirement etc. I'll figure out a way for bringing it back.
close #2 converted Builder into an interface. ResourceAnalyzers may grab
an instance calling newBuilder() on IndexableResource passed to them.