Add abort if snapshot is above certain size in Weka v3.14

[adamuk01]

Weka v3.14 introduces a new feature where it can tell you how big a snapshot upload should be. Perhaps we could have a feature where if a snapshot is above a certain size. It does not upload it. This gives the users time to figure out why the snapshot is too large and clean it up. Before it is committed to OBS. However it would need a good way to alert the users that that snapshot has not been uploaded, as obviously the next snapshot would contain the same data (plus more).