Add basic support for Durable Task Scheduler resources

[philliphoff]

Adds basic support for Durable Task Scheduler (DTS) resources:

• Exposing DTS resources within their own group in the Azure resources tree view
• Exposing task hub child resources for each DTS resource
• Support for displaying task hub properties and browsing to the task hub in both the Azure portal and DTS dashboard

Notes:

• DTS resources are exposed using the v2 Azure resource groups API (a departure from Functions resources)
• This PR is dependent upon DTS support being added to the Azure resource group API
• This PR is waiting for some remaining UI assets before it's ready for committal
  • We've decided this is fine for now and will update the assets if/when we get them.

[philliphoff]

With the Azure Resource Groups extension update committed and published, it looks like we can move on with this, too.

[philliphoff]

@alexweininger Do you know when the next release will be?

[alexweininger]

I'll have to coordinate with @nturinski to plan a release.

[nturinski]

@alexweininger Do you know when the next release will be?

I am trying to get a small release out this week for Functions. There are small things that partners would like us to include.

[nturinski]

@philliphoff Hey Phillip, we will have to delay the Functions release by a week. I forgot, but our testing team is out this entire week. Sorry about that; I'll make sure we have it out next week.

[philliphoff]

@nturinski Not a problem. That might even give me a chance to get in some additional resource management features.