Branch names of the form 'foo/bar' are problematic because we use the branch names as project names, and '/' is an illegal project-name character.

We can't simply URL-escape '/' because '%' is also an invalid project name character.

For simplicity, my current plan is to simply hash the name, if it contains a '/', and set the display name to be the branch name. This should allow us to be backwards compatible with projects currently instantiated by the project factory, while starting to support '/' branch names.