Error when running the basic producer sample

When I run the basic producer sample according to the docs, I get this error:

```
/Users/ttt/repo/ratingbutler/kinesis/amazon-kinesis-client-nodejs/node_modules/aws-sdk/lib/request.js:31
throw err;
^

TypeError: "callback" argument must be a function
at exports.setTimeout (timers.js:327:11)
at /Users/ttt/repo/ratingbutler/kinesis/amazon-kinesis-client-nodejs/samples/basic_sample/producer/sample_producer.js:101:11
```

The offending line is in 101 where the pass in param is not a function. I will open a PR to address this.

Start in samples/basic_sample/producer/sample_producer.js at line 101 and compare the timer call with the documented basic producer flow. Run the basic producer sample as described in the docs; done means it starts without the callback TypeError and the existing sample behavior remains intact.

Written by the indexing model from the issue text.