Link API should allow to add result data for convenience

[pedrocamargo]

Purpose of use
Allowing full manipulation of links with easy access to results.

Is your feature request related to a problem? Please describe.
I can see this being convenient when doing work on network resilience, where one may need assignment information to decide what to do with particular links

Describe the solution you'd like
Same API, but direct access to assignment results (fields/values)

Describe alternatives you've considered
It is easy to do it manually in memory.

Additional context
This opens the doors for future results (e.g. select link analysis)