Nodes are currently named using this pattern:

EC2 (Your cloud name) - Your AMI Name (i-123456)

There is other software that consumes `env.NODE_NAME` (like the P4 Plugin) and the spaces can cause problems. Can we have support for changing the node naming pattern?

I notice that if `Jenkins.checkGoodName()` fails, it will name the node after the instanceId alone. If I knew of a way to short-circuit that method I could achieve this without any code changes.

This blocks us from using the EC2 Plugin as we are unable to get the nodes to play nicely with our source control system (Perforce).