Remove unused ProjectState#color_class method
Clean up header on project index page
Display a project's next step to the owner

This UX change is based on alpha test feedback.
See the images attached to:
https://bitlab.cas.msu.edu/redmine/issues/1217
Remove user and group blocking

This feature is full of extremely complicated code, and in practice
everything that it does can be done by the site admin from the rails
console. Blocking users and groups is a stretch goal that should be
saved for future versions.