[StarCluster] createimage broken in github repo

[Justin Riley]

Hi Dan,

> e.g. in the S3ImageCreator object, you request 
> "self.ec2.aws_access_key_id" ....   which causes an AttributeError. 

Good catch. Looking through the code it was only in the S3ImageCreator 
class that I was referencing aws_access_key_id instead of aws_access_key 
but it really should be aws_access_key_id in general. Fixed in github.

> ... so of course, nothing happens.  (Same is true for EBS instances).  
> I'm sure you had a reason for doing this .... but

This was for testing purposes.  Fixed in github.

Thanks,

~Justin