Repeated loc() in complexes

[tythomson]

The location is repeated for each component in a complex, which makes the BEL expression very verbose and hard to visually parse. E.g., see R-HSA-350158.1. Can we list only the location for the complex, rather than the location for each component of the complex? Note that some complexes have components in different compartments, so this simplification cannot always be done. Eg. R-HSA-77283.1.