Add note about audience for paper to introduction

[vsoch]

After the rounds of edits are finished and the paper is in some ready state, I would like to give one more read through, and also take a shot at adding a section to the beginning that clearly defines the audience for the paper - likely focused on single application containers for data scientists.

[nuest]

So would I! With the hiatus over January/February, it should be possible to "kill some darlings", because shortening is really needed and I'm more and more convinced we need to through out content.

@vsoch What do you think - would you do the "audience" first and then see what does not fit that audience, what goes to far? Or should we have a call to close the open issues and just go through each rule and see how we can reduce it to the gist?

[vsoch]

I’d be good with going through and doing another PR to chop out some things - given the number of authors I think that asynchronous communication/review will be much more efficient than having a call.

[nuest]

@vsoch This is not closed yet, but I think the content is there - it just needs "sharpening" and probably the scope is a bit repetetive (and too long).

[vsoch]

So do you want me to take a look now (or wait a bit longer?)

[vsoch]

See #57

[nuest]

The audience and scope is much better described now, albeit quite long.