Initial commit of vCD cmdlets and related tests

[shamsway]

Description

initial support for VMware vCloud Director (vCD) API endpoints in CDM

• Added cmdlets Update-RubrikVCD, Set-RubrikVCD, Restore-RubrikVApp, Protect-RubrikVApp, Get-RubrikVcdTemplateExportOptions, Get-RubrikVCD, Get-RubrikVappSnapshot, RubrikVAppRecoverOptions, Get-RubrikVAppExportOptions, Get-RubrikVApp, Export-RubrikVcdTemplate, Export-RubrikVApp and related tests as requested in Issue 273
• Updated Get-RubrikSnapshot to support vCD vApps
• Misc bug fixes and typos corrected

Related Issue

#273

Motivation and Context

Why is this change required? What problem does it solve? Add new functionality to SDK

How Has This Been Tested?

• Extensive manual testing from macOS against CDM 5.0 and 5.1EA and vCD 9.5
• Unit tests added

Types of changes

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

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

Go over all the following points, and put an x in all the boxes that apply. If you're unsure about any of these, don't hesitate to ask. We're here to help!

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTION document.
• I have updated the CHANGELOG file accordingly for the version that this merge modifies.
• I have added tests to cover my changes.
• All new and existing tests passed. Tests passing when run locally, but failing on AppVeyor

[mwpreston]

I've looked over code and made some changes listed below. That said, I'll let @rfitzhugh validate the actual functionality as I feel like I could possibly break something :)

• Added some code around the Relic switch
• Also removed -Depth from some of the ConvertFrom-JSON statements in the tests as that param wasn't available pre PowerShell 6.
• Changed some tests which referenced .length to use .count as it was evaluating to null when only one result was returned.
• All tests passing now

[rfitzhugh]

Made some small documentation changes, otherwise LGTM.

[rfitzhugh]

Is it intentional that you use Vcd when referencing templates but VCD when referencing the server?

[shamsway]

Generally I try to use vCD in documentation or anything that is not actual code. Within CDM Vcd is typically used in object IDs and other places. Cmdlet names typically use UpperCamelCase, so I will do a quick pass and make sure there is consistency, at very least.

[rfitzhugh]

@shamsway I left one comment. Once conflicts are addressed, should be good to merge.

[jaapbrasser]

Reviewed and approved, ship it!