message: Add difficulty descriptions
  (For 8.0.0 release! Not in use yet!)
diff: "LABEL_INVOICE": "Invoice",
  "TITLE_SCORE_BOARD": "Score Board",
  "LABEL_DIFFICULTY": "Difficulty",
  - "LABEL_STATUS": "Status",
  + "LABEL_1_STAR_DIFFICULTY": "Trivial",
  + "LABEL_2_STAR_DIFFICULTY": "Easy",
  + "LABEL_3_STAR_DIFFICULTY": "Medium",
  + "LABEL_4_STAR_DIFFICULTY": "Hard",
  + "LABEL_5_STAR_DIFFICULTY": "Dreadful",
  + "LABEL_6_STAR_DIFFICULTY": "Diabolic",
  + "LABEL_CHALLENGES": "Challenges","LABEL_STATUS": "Status",
  "STATUS_UNSOLVED": "unsolved",
  "STATUS_SOLVED": "solved",
  "STATUS_UNAVAILABLE": "unavailable",
  