Support open types and dynamic properties

[maboivin]

Dynamic properties support has been added to the OData client 7.7.0, See this blog post for more details.

To support this new feature:

• The Microsoft.OData.Client dependency needs to be updated to the latest version (7.9.0).
• The ODataT4CodeGenerator needs to be updated to the one in the OData connected service which will give access to set a new property called EmitContainerPropertyAttribute to true.

On a side note, I was able to make it work by looking at the current code and removing the dependency on the FilesManager from the new ODataT4CodeGenerator from the OData connected service.

Do you think it's something that could be added for the next version of the driver?