Allow to save/load query results

[lambdamusic]

Similar to what pickle does with Python objects.

• https://stackoverflow.com/questions/2259270/pickle-or-json
• https://www.benfrederickson.com/dont-pickle-your-data/

[lambdamusic]

res = dsl.query(q)

# save

import pickle
with open('filename.pickle', 'wb') as handle:
    pickle.dump(res, handle)

# => can be packed into res.save(filename) 

Then loading

# full syntax
with open('filename.pickle', 'rb') as handle:
    b = pickle.load(handle)

# => can be packed into 

dsl.load(b) # => returns a dimcli.core.api.Result() object preloaded with data

[lambdamusic]

https://digital-science.github.io/dimcli/modules.html#dimcli.core.api.DslDataset.to_json_file