JCLOUDS-664:Implement OSImageToImage Function

implement OSImageToImage Function.
Changes to API implementation
1- Added PublisherName to OSImage
2-Changed Locations list to Location 
This should be the "real" ID of the image in the provider (usually the same as the *id* field, but sometimes in jclouds we encode the region as part of the id). Is this publisher name the *real* and *unique* id of the image in the provider?