Build parameter should be in badge link

[Carreau]

By mistake I ask to build the binder-example without checking the requirements.txt dependencies.

after that all instances launched by clicking on the badge where missing seaborn.

I think that each set of option selected should get a different url, with possibly a special url that targer the "latest" build. but otherwise people playing with binder.org and repo might just break other people links.

[andrewosh]

Definitely a big issue right now. Think your suggestion is the right way to fix this. Another alternative is to use GitHub credentials on the build page, so you can only build repos with the right permissions. The pro here is that the repo owner would select the "right" dependency file/services. That seems too restrictive though.

The only downside of this is that we'll have to maintain multiple images per repo. When it comes to dependency files, it's unlikely that more than one will apply to any given repo, so the docker build will likely fail in all other cases. When it comes to services though, this approach will lead to nasty combinatorial issues because we'll have to build a separate image for every set of included services.

The trade-off then is being overly restrictive on who can build images vs. having to manage a set of images that could grow exponentially in the number of services we provide.