Fixed RootModule bug

[anmenaga]

PR Summary

Some PS modules do not specify RootModule in their psd1.
In such cases Get-Module fills in RootModule with full path to psd1, which is misleading for discovering class-based resources.
This was causing internal failures in PsDscAdapter.
This PR fixes that with explicit check for such condition and adds some tracing to make diagnostics easier.

[michaeltlombardi]

What about cases where people split their module code without using NestedModules?

For example, the pattern built by the DSC Community has base classes etc defined in a sub-module and has using/import statements to retrieve the code:

• SqlServerDsc root module
• SqlServerDsc module manifest

[anmenaga]

What about cases where people split their module code without using NestedModules?

For example, the pattern built by the DSC Community has base classes etc defined in a sub-module and has using/import statements to retrieve the code:

• SqlServerDsc root module
• SqlServerDsc module manifest

1. strictly speaking this is out of scope of this particular bug;
2. I've looked through the PSAdapter code and your example module; and looks like such cases should be handled just fine when...
3. ... class-inheritance will be implemented.
4. Thanks for a good example module; that will help with development.

[SteveL-MSFT]

We can address other issues as separate PRs