Bump virtualenv version in install_rally.sh
Bump virtualenv version in install_rally.sh

install pip/setuptools/wheel manually in virtualenv.

Change-Id: I04cb8b0129f4b05b6055c7da34424f6387dd6e1b

yeming233/rally,openstack/rally,openstack/rally,openstack/rally,yeming233/rally,openstack/rally