Bug # 1205425 - Add Fedora image to basic install.

Added downloading of Fedora cloud image to instructions for Glance setup
in the Yum version of the guide.

Change-Id: I2850add70727401c5acb05408bb60f27b9945261
Fixes: 1205425
Merge "Bug # 1205425 - Add Fedora image to basic install."