Paste Auto-Map logic

Summary

When you paste into relations attributes, the following logic is used to map objects and relations:

• If the AMI clipboard contains relations, then the pasted items are mapped to the relevant relation slots (for example, if the clipboard contains a 'Main Image' asset relation then it will be pasted into the 'Main Image' slot).
  If relations have been selected then the pasted items will also be mapped to those relations.
• If the AMI clipboard contains objects, then auto-map will use the selected relation.
• If there is a single object on the AMI clipboard, then it will be auto-mapped to any selected related objects (replacing them) or empty relation slots.
• If there are several objects on the AMI clipboard, then auto-map will only work if you have either a single 'allow multi instance' relation selected or one or more objects selected within a single single 'allow multi instance' relation. All of the clipboard objects will be mapped to the selected relation.