Nicer interface for browsing captured problems

[randomir]

Sometimes the problem/solution is not explicitly available in user's code. Thanks to low-level data capturing we still have access to these (in dwave.inspector.storage), but the interface is quite awkward. For example to visualize one QMI:

dwave.inspector.storage.index_resolved_problems()
problem_id = list(dwave.inspector.storage.problemdata.keys())[0]
dwave.inspector.show(problem_id)

Few fixes possible:

• order all problems in time
• write interface for browsing problems, without the need for explicit indexing
• extend show to accept problem_index: int (or maybe even strings like "last" and "first"?)

Note this can handle only QMIs for now. For fully automated logical problem inspection, we need to extend data capture to samplesets.