add sayed's template validation package and hook it up

[baronfel]

Proposed Changes

The same tool that gave me the info for my last set of revisions now has an MSBuild task for template validation. I've hooked it up here, but we shouldn't commit this yet: there's a bit of manual work a user has to do in order to get the validations to run, and I want to work with @sayedihashimi to make this a very simple 'just add package and go' experience.

Types of changes

What types of changes does your code introduce to MiniScaffold? Put an x in the boxes that apply

• [ ] Bugfix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist

Put an x in the boxes that apply. You can also fill these out after creating the PR. If you're unsure about any of them, don't hesitate to ask. We're here to help! This is simply a reminder of what we are going to look for before merging your code.

• [ ] Build and tests pass locally
• [ ] I have added tests that prove my fix is effective or that my feature works (if appropriate)
• [ ] I have added necessary documentation (if appropriate)

[TheAngryByrd]

@baronfel think this is still work trying to merge in?

[baronfel]

yes, but also possibly these new authoring tools!