Work CI-CD

- Migrate build image to windows latest.
- Request to GitHub API are now authenticated.
- Split clone step in two: libs and IoT bindings.
- Clone of class libs is now made to `libs` folder.
- Nuget restore is now a single step with a wildcard on filter to catch all solutions.
- VSBuild is now a single step for all class libs.
- Update docfx filters to catch docs for class libs in new location.
- Add new docs to exclusion list for build trigger.
- Minor style improvements in AZDO yaml file.

Author: josesimoes