Worker status is misleading

[armish]

Worker status says "uploading..." even though file is already uploaded:

It is a little bit misleading as it is just workers doing their magic on the file at this point. Potential solutions:

• make each worker implement a short description of what is doing and surface that (e.g. "Extracting genotypes" for the first worker or "Annotating mutations" for the second one)
• show a progress bar/text that says how far we are in the process (e.g. "Processing 1/5..." or "20% done", "=>----")
• simply use "Processing" instead of "Uploading"
• ...