ability for users to define details used when checking status of a snapshot build

[ryankwilliams]

Today paws has a maximum number of 30 attempts and delays 20 seconds between each attempt when checking if a snapshot is finished building. There is occasions where these default values need to be expanded in order for the snapshot building to complete. Instead of just increasing the default values. It would be nice for the user to be able to define these.

This issue is to add the ability for user to declare these values within there system resource block.