Add a way to collect cached results

[csala]

• SDGym version: 0.3.0

Description

Apart from producing a single dataframe or CSV file with the scores obtained by all the Synthesizers, SDGym has the option to store intermediate results, scores and error logs as the different tasks are run, which are kept inside the cache_dir. However, if the sdgym process is cut for some reason, there is no way to find all the intermediate results and put them together as a single CSV file again.

It would be interesting to have a collect_results function and an sdgym collect command that would do this job and allow producing a single scores CSV file from a collection of intermediate cached results.