Add license support in CM scripts and add "get cognata dataset" script

[gfursin]

Requested features:

• CM scripts must show licenses and let user accept or reject them (should be used for the private MLPerf inference models too)
• We should have variations for _full and _short datasets
• We should have variations to use different URLs

We can either add a key "must_accept_license":True in CM script meta or check if LICENSE.md file exists inside CM script or both. Another point is that we may need different licenses per variation (i.e. _full dataset may need license while _short may be open to everyone) ... @arjunsuresh - let's discuss how to create this prototype for the next ABTF meeting.

CC: @kaspermeck-arm

[arjunsuresh]

yes Grigori. I think we should show the license in the same way AndroidSDK tool is doing.

[gfursin]

Agree! We are now busy finalizing CM for MLPerf inference to release it next week - as soon as it's done, let's prototype it - I can help with that ...