Add Ability to Pick Objects to Import

[jdrew82]

Environment

• DiffSync version: 1.6.0

Proposed Functionality

It would be useful if there was a screen that showed the objects to be imported from your DataSource and allow you to select the objects out of the batch you wish to import. Due to large datasets we would need the ability to pick groups of objects. Similar to #37 it'd be useful to filter the objects to import either before the Job starts or once the diff has completed and you can see what CRUD operations would occur.

Use Case

As a end-user I'd like the ability to pick individual objects, either Sites or Devices or related, and have only those imported. This would be extremely useful when there's only one change in a SoR that I want to import.