Update dev_setup.py script
Update dev_setup.py script

1. Make it executable
2. Update shebang
3. Colorize the output and improve the readability

QingChenmsft/azure-cli,QingChenmsft/azure-cli,samedder/azure-cli,yugangw-msft/azure-cli,yugangw-msft/azure-cli,yugangw-msft/azure-cli,QingChenmsft/azure-cli,QingChenmsft/azure-cli,samedder/azure-cli,samedder/azure-cli,samedder/azure-cli,yugangw-msft/azure-cli,yugangw-msft/azure-cli,yugangw-msft/azure-cli