Update to accommodate CatalogService restructuring and breaking API changes

[jsavell]

Upcoming CatalogService changes will require changes to GIFMButtonService.
https://github.com/TAMULib/CatalogService/pull/98/files

In particular, but not necessarily only:

• GIFMButtonService will need to start using CatalogService's domain objects.
• GIFMButtonService will need to let Spring de-serialize the CS data instead of manual object mapping
• GIFMButtonService should be refactored to stop using reflection in this magic method for finding the value by property key

[jsavell]

The first item was completed while the other two turned out to be unnecessary for the standalone Catalog Service re-implementation.

I think this issue can be closed since there's no requirement for completion of the other two items.