Add a local flask server to analyze datasets

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Currently it is a pain to analyze local datasets, therefore I built this little flask server to help with that.
The server is just a bare-bones version of what it could be and supports only a couple of datasets as of now, but this is easily updatable. Also there are still some bugs in the userflow if one is not patient enough to wait until loads finish (the frontend actually does not show if something happens in the background).

Some notes:

• the server reuses cached datasets (and indicates the locally found datasets with (local))
• selected but not cached datasets are loaded in the background
• the userflow is still rough around the edges, so expect that you need to restart if you get an error.

Here a little taste what the server is capable of: