Update tr-be-script.sh

Add some Required Packages 
Add Installing System Update

add 
sudo chmod 777 ~/Downloads/Python-2.5.6/Lib/plat-linux3
rm -Rf ~/Downloads
can delete all temporary files,include /Downloads/Python-2.5.6/Lib/plat-linux3
Merge pull request #3 from ruling/patch-2

Update tr-be-script.sh