Dynamic expando object

I switched from using Dynamic to using ExpandoObject because ExpandoObject offers better serialization support.

Fetch Many Example
```c#
public class FetchStuff : OutTask<FetchStuff.Output>
{
    public class Output
    {
        public Object[] Stuff { get; set; }
    }

    public override void Execute()
    {
        using(var connection = Db.Connect("MyConnectionString"))
        {
            const string sql = "......."
            Out.Stuff = Db.GetMany(connection, sql);
        }
    }
}
```

Fetch One Example
```c#
public class FetchThing  : OutTask<FetchThing  .Output>
{
    public class Output
    {
        public Object Thing { get; set; }
    }

    public override void Execute()
    {
        using(var connection = Db.Connect("MyConnectionString"))
        {
            const string sql = "......."
            Out.Thing = Db.GetOne(connection, sql);
        }
    }
}
```