Add a basic test for nested examples.

Part of #2.

src/seed.ts

@@ -51,7 +51,6 @@ const expandSeedData = (idFromParent : SeedID, data : SeedData, result : Expande
 		(resultData as any)[key] = subReference;
 	}
 
-	//For now just add all seeds, an effective pass-through
 	result.seeds[id] = resultData;
 	return id;
 };

test/base/test.ts

@@ -218,6 +218,32 @@ describe('Garden smoke test', () => {
 		});
 	});
 
+	it('a nested seed is legal', async() => {
+		const garden = loadTestGarden([]);
+		//We can't just do a manually typed SeedPacket because its type doesn't
+		//explicitly allow nesting due to the error descrbied in
+		//makeNestedSeedData, issue #16.
+		const packet = seedPacket.parse({
+			version: 0,
+			seeds: {
+				'': {
+					'type': 'log',
+					'value': {
+						'type': 'log',
+						'value': true
+					}
+				}
+			}
+		});
+		garden.plantSeedPacket('test/base/foo.json', packet);
+		const seed = await garden.seed('');
+		const result = await seed.grow();
+		const golden = true;
+		assert.deepStrictEqual(result, golden);
+	});
+
+
+	//TODO: a named inner value doesn't pass.
 });