Add required to submissions
Update the step progress when a user finishes a submission
Update step progress when a submission is made
Add complete method for introduction steps
Add route for completing introduction steps
Add getters for the first lesson for the introduction steps
Add method for getting the acceptable submissions for a user
Links now go to the complete method which redirects to the next step (intro or actual step)
Display completed intro steps. Active overrides completed. Don't highlight steps when on introduction steps
Switch to status_for_user
Add in progress color
Add in progress methods for steps, lessons, introduction steps
Accept nil or false for completed to determin in progress
Color the project link black. Finish project completion tracking
Merge branch 'mark-projects-show' of github.com:teamleada/teamleada.com into mark-projects-show