No need to require credentials/STS from providers
Remove use of bare enum keyword
Update coffee-script dependency version
Support getSignedUrl when using V4 signing
Throw an error when getSignedUrl Expiry time is greater than a week in SigV4
Various pagination fixes
Update CloudWatch to SigV4
Update documentation and pagination rules for source models
Fix S3 integration test that causes test to break early
Revert change to CloudFront signature version for 2012-05-05
Update EC2 API
Update SES documentation
Add support for dead letter queues in AWS.SQS
Rewrite test to work in browser mode
Remove unused ActivateLicense operation
Bump version to v2.0.0-rc9
Match EOL in Windows friendly way
Default to using maxSockets setting from https.globalAgent.

This change allows the SDK to inherit the maxSockets property
from the global agent in Node.js so that users do not have to
pass in a custom agent to increase maxSockets. Instead, this
change allows users to do the following to increase maxSockets:

```javascript
require('https').globalAgent.maxSockets = 20;

var s3 = new AWS.S3();
for (var i = 0; i < 20; i++) {
  s3.getObject(params, function (err, data) { /* ... */ });
}
```

Fixes #224
Explain url variable in SQS example
Don't clear error/data properties on retry.

Allows other retry listeners to inspect error/data before retrying.