licenses for web and workshop materials

[bob-carpenter]

we should indicate what the license is on all the material, including the workshop handouts

[syclik]

@bob-carpenter, do you have a preferred license for it? I'm happy following your lead.

[bob-carpenter]

It's now up to whoever wrote the various bits. We can talk about policy for posting stuff here, but it's not even advertised on our site, so I'm not going to worry about it. By default, I believe everything's copyright the author(s) and provides no license for users.