Export multi methods

[Gijsreyn]

PR Summary

Address issue #578. Additional class can be added if needed to have only one export method.

PR Context

[Gijsreyn]

@SteveL-MSFT Hi Steve, I was actually a bit suprised my change broke the build. The reason is, after debugging and checking out the history on #556, I'm doubting if the change there was fully tested.

If I add the following line in the Invoke-DscOperation:

if ($DesiredState.properties)
{
    # set each property of $dscResourceInstance to the value of the property in the $desiredState INPUT object
    $DesiredState.properties.psobject.properties | ForEach-Object -Process {
        $dscResourceInstance.$($_.Name) = $_.Value
    }
}
($dscResourceInstance | ConvertTo-Json -Depth 10 -Compress) | Write-DscTrace -Operation Trace

I could see this:

Clearly the properties are added to the output result set. That's why the tests are failing. Shouldn't these be filtered out?

[anmenaga]

The diagnostic code is checking the wrong thing; 'filtering out' is done by constructing a new hashtable result object.
For 'Get' operation it should be something like:
($Result | ConvertTo-Json -Depth 10 -Compress) | Write-DscTrace -Operation Trace
that is inserted before line 477.

Similarly for 'Export' operation - $Result_obj before line 498.