Copy Prototype

This is just a prototype for early feedback.  Some anticipated concerns:

- Copying objects is hard because of relationships between objects.  I'm choosing to only allow non-delegated, non-ID properties.  I think this might be sufficient for a first pass and maybe all that can be done as a general solution.
- The test is very minimal.  I would add coverage for all branches in `Genome::Command::Copy`.
- This differs from the other `Genome::Command::Crud` commands in that it is opt-in.  This is only due to my skepticism at the moment of having a generalized copy command.
- This uses fatal warning to avoid incorrect usage of the Perl operators, e.g. `.=` vs. `+=`.
Are you intending to allow 'property=' to set the property to an empty string? This seems reasonable to me, but you may want to add it to the documentation?