Added registry of top-level descriptors
Addressed comments
Fixed duplicate call to add to profile registry
addressed comments
Addressed comments
Addressed comments: Added extra check on raw_profile registry and unchained the add to registry and add to raw profile registry.
I don't really like moving it into the add to registry method with the condition as that makes it more complicated.
Return descriptor at end of registration
Merge pull request #40 from mdsol/feature/top_level_descriptors

Added registry of top-level descriptors