ISSUE#1 - Can't have multiple AWS-SQS components

Hi Dmtrs,

I'm using your great library for a while, and I feel only gratitude  for sharing it with the rest of us but there are a couple of thing that should change.

1st Issue

At the [AWSQueue](https://github.com/dmtrs/yii-aws-sqs/blob/master/AWSQueue.php#L10) you have the `$sqs` instance as static.

This means that any other  `AWSQueue` instances will share the same `AWSQueueManager` component.
What if you want to have a second QM (Queue Manager) that using a totally different AWS credentials? 

2nd Issue

At the [AWSQueue::sqs()](https://github.com/dmtrs/yii-aws-sqs/blob/master/AWSQueue.php#L73) you are expecting a single component with the `sqs` identifier .

This means that when you create a second QM it will use always the first to send the messages at the sqs, which might be ok if both are using the same credentials.


Best Regards
YT