Added option to specify disk by 'Location' property

[ianwalkeruk]

• Updated Get-DiskByIdentifier to recognise 'Location'
• Updated Get-DiskByIdentifier to use switch statement
• Added tests for get disk by Location

Pull Request (PR) description

This Pull Request (PR) fixes the following issues

Task list

• [x] 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).
• [x] Resource documentation added/updated in README.md in the resource folder.
• [x] Resource parameter descriptions added/updated in schema.mof and comment-based help.
• [x] Comment-based help added/updated.
• [x] Localization strings added/updated in all localization files as appropriate.
• [x] Examples appropriately added/updated.
• [x] Unit tests added/updated. See DSC Resource Testing Guidelines.
• [x] Integration tests added/updated (where possible). See DSC Resource Testing Guidelines.
• [x] New/changed code adheres to DSC Resource Style Guidelines and Best Practices.

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This change is 

[msftclas]

All CLA requirements met.

[codecov-io]

Codecov Report

Merging #212 into dev will not change coverage. The diff coverage is 100%.

@@        Coverage Diff         @@
##           dev   #212   +/-   ##
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  Coverage   95%    95%           
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  Files        7      7           
  Lines      978    978           
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  Hits       937    937           
  Misses      41     41

[PlagueHO]

Great stuff @ianwalkeruk - I'll start the review once the tests are passing. Very cool to get this feature added.

[ianwalkeruk]

Great stuff @ianwalkeruk - I'll start the review once the tests are passing. Very cool to get this feature added.

Thanks - it's a lot deeper into Pester than I've ever been before, which is enjoyable but slow!

[ianwalkeruk]

I had to remove the integration tests, because the MSTF_Disk CIM resource had a null value for Location on the Appveyor platform. Unit tests all work fine.