Fix sample Rally plugin
Fix sample Rally plugin

_generate_random_name() in Rally is being replaced by
generate_random_name().

Implements blueprint: consistent-resource-names

Change-Id: I2939a8ee10be6f5e8e6cfee7e4adb65d96e4f88f

klmitch/glance,dims/glance,openstack/glance,rajalokan/glance,openstack/glance,stevelle/glance,klmitch/glance,stevelle/glance,rajalokan/glance,openstack/glance,dims/glance