Not at this time - below is a screenshot of the supported data file types you can upload. I understand your point and it would be nice to have some sort of content management so you can include addition items and keep them all in one place - if you would like - you can use the feedback link in the menu on the left and submit this question to them and see what the plan is in this area. I will also tag the cloud team sarahkohler kha to see what they may say on this thread.
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