🏫 add license info & other key documents

[stevejpurves]

Aligning thebe-core with thebe license

[stevejpurves]

@choldgraf I've moved the license over from thebe as I think the same would apply here

What other documents are we missing from this an an EB repository?

• The original thebe has a code of conduct document https://github.com/executablebooks/thebe/blob/master/CODE_OF_CONDUCT.md which should at least be updated with a new contact, but I don't see this as a feature on other EB repos? potentially related to Define a Code of Conduct team and have a dedicated email for it team-compass#2?

• I'm not adding a CHANGELOG until we get to a proper release, which will be when thebe starts to consume this.

[stevejpurves]

Also @choldgraf is there an appropriate way to update the Acknowledgments section to reflect the latest round of work, indicating involvement and funding source?

[choldgraf]

Some quick thoughts on the acknowledgements section below.

For the Code of Conduct, how about we point it to the page in executablebooks.org that is being added by the PR here:

• https://github.com/executablebooks/meta/pull/770/files

I also opened up another issue to track attribution of organizations in our Team page. Would love thoughts there:

• Add a gallery of organizational support for this project meta#774