Method snapshot

benchmarks/memory.js:34–45

* Takes a memory snapshot

(label)

	 * Takes a memory snapshot
	 */
	snapshot (label) {
		this.forceGC();
		const usage = process.memoryUsage();
		const snapshot = {
			label,
			timestamp: Date.now(),
			...usage
		};
		this.snapshots.push(snapshot);

		return snapshot;
	}

	/**
	 * Calculates memory difference between two snapshots