rsTo = new DefaultRevisionStore(new InMemPersistence());
rsTo.initialize();
CopyingGC gc = new CopyingGC(rsFrom, rsTo);
MicroKernel mk = new MicroKernelImpl(new Repository(gc, new MemoryBlobStore()));
revs[0] = mk.commit("/", "+\"a\" : { \"c\":{}, \"d\":{} }", mk.getHeadRevision(), null);
revs[1] = mk.commit("/", "+\"b\" : {}", mk.getHeadRevision(), null);
revs[2] = mk.commit("/b", "+\"e\" : {}", mk.getHeadRevision(), null);
revs[3] = mk.commit("/a/c", "+\"f\" : {}", mk.getHeadRevision(), null);