Extract components and add more tests

bin/more_elaborate_example.php

@@ -6,10 +6,11 @@ use React\EventLoop\Factory as EventLoopFactory;
 
 require_once __DIR__ . '/../vendor/autoload.php';
 
-// Create our own EventLoop and limit and supply them to the builder
 $loop = EventLoopFactory::create();
-$limit = new ConcurrencyLimit(4);
-$context = ContextBuilder::create()->withEventLoop($loop)->withLimit($limit)->build();
+$context = ContextBuilder::create()
+	->withEventLoop($loop)
+	->withLimit(ConcurrencyLimit::atMost(4))
+	->build();
 
 $context->on('booted', fn() => print("🚽 Toalett Multiprocessing Context\n"));
 $context->on('congestion', fn() => print('C'));
@@ -17,7 +18,6 @@ $context->on('congestion_relieved', fn() => print('R'));
 $context->on('worker_started', fn() => print('+'));
 $context->on('worker_stopped', fn() => print('-'));
 
-// Submit a fake job every second
 $loop->addPeriodicTimer(1, fn() => $context->submit(fn(int $s) => sleep($s), random_int(0, 10)));
 
 print("Press CTRL+C to stop.\n");