Fix incorrect disk_info usage of API and ApiWrapper classes

Fix the usage of the Geometry structure from struct.rb as well
as call to the get_info method in the api.rb - both in the API class.

Increment the version of the gem to 1.0.1 due to this change.
@Fryguy @roliveri please review

version should be bumped in it's own commit which is tagged and released.  Can you remove this from teh PR?