Allow access in main scope to import scoped structs or record properties

[arosboro]

When a transition circuit defines an input or output with another program_id from an import in the form program.leo/RecordName.record you have to rely on program.leo to have helper transition functions to return properties on the record. I propose accessing the properties directly in main or allowing the imports helper functions to be called from main.

Not sure what sequence ARC this proposal should be given.