Update README.md

[hc8756]

##Purpose
Updated README to fulfill following requirements:

• Does the README describe how multiple instances of the client connect to the service at the same time, and how the service tells them apart? Check the corresponding parts of the code to see if it looks like multiple instances of the clients can indeed interact with the service simultaneously. Your README should explain how to connect the instances of the client to your service. Make sure your service can interface to multiple instances of the same client running simultaneously; your README should discuss how it does this, particularly how it tells the clients apart.
• Is there useful documentation about what a hypothetical third-party developer would need to do to develop their own client for the team's service?

[jag2430]

Looks good, merged.