Error handling improvements

[glennmatthews]

• Catch Django ValidationError when creating/updating Nautobot data. Fixes ValidationError crash on rack import #4
• Catch Pydantic ValidationError when creating/updating internal data model. Fixes pydantic.error_wrappers.ValidationError crash on device import #5
• Add ObjectNotFound error handling for GenericForeignKey fields. Fixes Command errors out with ObjectNotFound exception #2
• Enable importing data exported from NetBox 2.10.5. Fixes Import of NetBox 2.10.5 JSON data #3
• Improve logging when errors are encountered during data loading
• Permit Devices with no name; add more fields to Device._identifiers to better distinguish device uniqueness
• Process templates after processing devices so that devices get initialized empty instead of pre-populated with components (since we will add the components ourselves)
• Fixed some incorrect definitions of the Service and PowerOutletTemplate models. Fixes Pydantic validation errors reported on import of Service and PowerOutletTemplate models #8.
• Populate the test data dump with additional data: Services, IPv6 addresses, and device component templates.

[jathanism]

Good to see the issue I ran into addressed!