Fail on artifact not reachable

[mvisonneau]

As of now, when the artifact is not reachable, the deployment hangs, whether on :

[10:50:00.63] Deployment started
[10:50:00.26] Reading infrastructure configuration...

or

[10:31:20.92] Creating [LaunchConfig_myapp] LaunchConfiguration...
[10:31:17.75] Following LaunchConfigurations have to be created: [LaunchConfig_dv2-ct-myapp]
[10:31:17.42] Following LaunchConfigurations are expected: [LaunchConfig_dv2-ct-myapp]
[10:31:17.41] Following AutoScalingGroups have to be created: [dv2-ct-myapp]
[10:31:17.00] Following AutoScalingGroups are expected: [dv2-ct-myapp]
[10:31:13.61] Deployment started
[10:31:13.23] Reading infrastructure configuration...

depending if the ASG/instances have been deployed already or not.

Having an error thrown or even logs when EM is not able to fetch the artifact would be a huge help.