Change WCF configuration to allow only the web app to access the agents

[sinelaw]

Currently anyone on the agent's network can connect without authentication and run executer actions. To increase security the WCF configuration can be changed to use public key security to verify that only the web app can connect to the agents.

For more information see http://msdn.microsoft.com/en-us/library/ms729700%28v=vs.110%29.aspx

We may need to switch from basicHttpBinding to another protocol to get this to work.