Changed herodownloader by a python script

More portable,
More readable,

Python is GREAT :D

Signed-off-by: Mattijs Korpershoek <mattijs.korpershoek@gmail.com>
Python script to download hero portraits

Finished the python script.
It now also generates the HeroDatabase.txt in a format which the Java
application understands, i.e. one heroName per line.

Signed-off-by: Mattijs Korpershoek <mattijs.korpershoek@gmail.com>