Add example of how to run start-crawl in docker

[ejulio]

From
scrapinghub/scrapinghub-entrypoint-scrapy#62

[ejulio]

@Gallaecio thanks for checking this one.
I've rolled back the docs changes and updated the text as you asked

[pawelmhm]

Thanks for adding this documentation!

Only problem I see is that commands needed to actually run container are quite complex, is there no way to somehow change architecture in a way that makes it possible to run container the same way as in Cloud locally with just one step? Or maybe add some separate library, shub-zyte-cloud where people can go and run someone single command like "make" or "please" and it will launch things. This is just an idea though, this documentation improvement looks very good on its own

[ejulio]

Hey @pawelmhm , I'll leave your comment hanging around on my notes.
I believe there could be a way to do something like that, but I'm not sure

[ejulio]

@Gallaecio can you merge this one? I don't have proper access :(