Log message to console to indicate copying has started

For long or slow copies, it appears the job has hung, as the plugin does not log any messages to indicate it has started copying.

e.g. in one case where i had misconfigured what to copy, and it was copying 10Gb of workspace, the job appeared to just hang. I thought it was a connectivity issue and tried lots of different things. It wasn't until i left it going overnight and the slave eventually ran out of disk space, that the plugin logged it's failure and i realised it had actually been copying files all that time.