Improve wizard download process

The current approach to download REST in the wizard:

• Download each page of REST resource
• Convert resource to the correct objects
• Check if there's next resource page to download, repeat the above steps
• Return collection of objects

One of the better approach would be:

• Download each page of REST resource and save them locally
• Check if there's next resource page to download, repeat the above step
• Convert resources to the correct objects
• Return collection of objects

This approach could potentially saving us if the download process is stopped before it's done.