This patch alters storage_policy.py to allow storage policies
to have multiple names. Now users are able to add a number of
human-readable aliases for storage policies. Policies now have
a .name (the default name), .aliases (a string of comma
seperated aliases), and .aliases_list (a list of all human
readable names). Policies will always have an .aliases value
if no aliases are set it will contain the default name.
The policy docs and tests have been updated to reflect changes
and policy.get_policy_info has been altered to display the
name and aliases
Change-Id: I02967ca8d7c790595e5ee551581196aa64552eea