Move test templates from DscResource.Template

We should move and update the test templates from here https://github.com/PowerShell/DscResource.Template/tree/master/Tests to this repo. For example the integration tests are missing in this repo.

Compare the Tests directory in DscResource.Template with the corresponding test structure in this repository, noting which templates and integration tests are absent. Review the existing test setup before deciding the destination and update scope; done means the relevant templates have been moved and the missing integration tests are present and usable here.

Written by the indexing model from the issue text.