code: public void useProject(String projectName) {
          removeProject(projectName);
          recentProjectsList.addFirst(projectName);
          while (recentProjectsList.size() > MAX_RECENT_FILES) {
              recentProjectsList.removeLast();
          }
      }
docs: Add given project filename to the front of the recently-used project
  list.
  
  @param projectName
  project filename