Add dapr debug configuration

[philliphoff]

Adds a custom dapr debug configuration that enables F5-style debugging of Dapr applications, simply by pointing to the dapr.yaml run file. Developers can debug existing Dapr applications or, via the preLaunchTask property, make the startup of the applications (e.g. via a dapr task) a prerequisite. Developers can also indicate that only a subset of the applications in the run file should be attached to (either via an inclusion or exclusion list, using the includeApps and excludeApps properties, respectfully).

{
    "version": "0.2.0",
    "configurations": [
        {
            "name": "Launch Dapr",
            "request": "launch",
            "type": "dapr",
            "runFile": "${workspaceFolder}/dapr.yaml",
            // "includeApps": ["csharp-subscriber", "node-subscriber"],
            // "excludeApps": ["python-subscriber", "react-form"],
            "preLaunchTask": "dapr"
        }
    ]
}

Resolves #273