NetAdapterPowerManagement: new resource

[gaelicWizard]

Pull Request (PR) description

New module to expose Disable-NetAdapterPowerManagement and related cmdlets, and to help me learn unit testing

NOTE: this is patch based off #496, so there's a lot of whitespace change.

This Pull Request (PR) fixes the following issues

• Fixes NetAdapterPowerManagement #461, forked from Added the ability to change the power options on the network adapter #219

Task list

• Added an entry under the Unreleased section of the change log in the CHANGELOG.md.
  Entry should say what was changed, and how that affects users (if applicable).
• Resource documentation added/updated in README.md in resource folder.
• Resource parameter descriptions added/updated in schema.mof
  and comment-based help.
• Comment-based help added/updated.
• Localization strings added/updated in all localization files as appropriate.
• Examples appropriately added/updated.
• Unit tests added/updated. See DSC Resource Testing Guidelines.
• Integration tests added/updated (where possible). See DSC Resource Testing Guidelines.
• New/changed code adheres to DSC Resource Style Guidelines and Best Practices.

---

This change is