Add ResumeRuntime command to client library

[josalem]

Update the documentation for the new Advertise protocol and implement the ResumeRuntime command on DiagnosticClient.

[josalem]

Was added in #1303. Code can be found here:

diagnostics/src/Microsoft.Diagnostics.NETCore.Client/DiagnosticsClient/DiagnosticsClient.cs

Lines 141 to 158 in a23c430

	internal void ResumeRuntime()
	{
	IpcMessage message = new IpcMessage(DiagnosticsServerCommandSet.Process, (byte)ProcessCommandId.ResumeRuntime);
	var response = IpcClient.SendMessage(_endpoint, message);
	switch ((DiagnosticsServerResponseId)response.Header.CommandId)
	{
	case DiagnosticsServerResponseId.Error:
	// Try fallback for Preview 7 and Preview 8
	ResumeRuntimeFallback();
	//var hr = BitConverter.ToInt32(response.Payload, 0);
	//throw new ServerErrorException($"Resume runtime failed (HRESULT: 0x{hr:X8})");
	return;
	case DiagnosticsServerResponseId.OK:
	return;
	default:
	throw new ServerErrorException($"Resume runtime failed - server responded with unknown command");
	}
	}