Pet achievements

These could help with encouraging people to buy pets, feed them, cuddle them (even others'!), and just make sure they're cared for! Some suggestions:

• Have (at least) 1 pet from every type;
• Adopt X pets; 
  • 5, 10, 25, 50
• Cuddle pets X times; 
  • 5, 25, 50, 100, 250, 500
• Cuddle X different pets;
  • 5, 10, 25, 50, 100
• Keep a pet happy for X days straight;
  
  • 3, 10, 20, 30, 40, 50
• Have a pet for X days (without them running away, ofc);
  • 7, 14, 30, 50, 100, 250

Just suggestions, of course!