Add note about how to start the console to run the README example.

Author: jkakar

README.md

@@ -4,13 +4,14 @@
 
 ## Features
 
-* Generated by [aws-codegen](https://github.com/jkakar/aws-codegen) using the same JSON descriptions of AWS services used to build
-  the [AWS SDK for Go](https://github.com/aws/aws-sdk-go/tree/master/models/apis).
-* Supports AWS services that use `json` and `rest-json` protocols.
+* Generated by [aws-codegen](https://github.com/jkakar/aws-codegen) using the
+  same JSON descriptions of AWS services used to build the
+  [AWS SDK for Go](https://github.com/aws/aws-sdk-go/tree/master/models/apis).
+* Support for most AWS services that use `json` and `rest-json` protocols.
 
 ## Example
 
-Listing Amazon Kinesis streams
+Listing Amazon Kinesis streams. Start a console with `iex -S mix`:
 
 ```elixir
 iex> client = %AWS.Client{access_key_id: "<access-key-id>",
@@ -36,10 +37,10 @@ iex> IO.inspect result
 
 * Run `mix deps.get` to install.
 
-
 ## Development
 
-Code is generated using the [aws-codegen](https://github.com/jkakar/aws-codegen) library, from the JSON descriptions of AWS services provided by Amazon.
+Code is generated using the [aws-codegen](https://github.com/jkakar/aws-codegen)
+library from the JSON descriptions of AWS services provided by Amazon.
 
 ## Documentation
 
@@ -63,4 +64,5 @@ mix test
 
 ## License
 
-&copy; 2015-2017 Jamshed Kakar <[email protected]>. See `LICENSE` file for details.
+&copy; 2015-2017 Jamshed Kakar <[email protected]>. See `LICENSE` file for
+details.