Update factorial.py

My function is adorbs. I want to pat its cute little head.
Update factorial.py
Merge pull request #1 from Gerdie/patch-1

Update factorial.py
Merge pull request #2 from Gerdie/master

Update dice.py
updated factorial.py with feedback
Update factorial.py

fixedy fixed
Added notes for dice.py
Added notes and additional challenge for factorial.py (recursion!)
Added New Exercise! 
bubblesort.py
Merge pull request #1 from cepstrum/master

Update Gerdie