Add "copy" button to execution cards

[jisantuc]

While Granary provides good safety against submitting commands that Batch jobs will think don't make any sense... it still doesn't protect users from typos. It would be helpful to have a copy button on the executions list so that when you, for example, copy the prefix to a key you need in s3 and forget to specify the object after that prefix... you can just copy and fill in the part that you messed up. I'm using the Granary UI to submit and confirm configuration for some Cloud Buster jobs, and I keep messing up in this particular way, and it's frustrating.