Allow named connections strings

[Ol-Wood]

Describe your suggestion
It would be great if the connections string property of the the WriteTo:AzureTableStorage section of appsettings would allow a named connection string that it reads from the root connection strings section of appsettings. Some other serilog sinks already provide this functionality.

So what I mean is:

{
  "ConnectionStrings": {
    "AzureTableStorage": " <connectionString>"
  },
  "Serilog": {
    "WriteTo": [
      {
        "Name": "AzureTableStorage",
        "Args": {
          "storageTableName": "<TableName>",
          "connectionString": "AzureTableStorage" // This value maps to property in ConnectionStrings section
        }
      }
    ]
  }
}