Add endpoint to get several bucketed values

Weather/Service/Models/WeatherReadingGrouped.cs

@@ -0,0 +1,21 @@
+using JetBrains.Annotations;
+using System;
+
+namespace ChrisKaczor.HomeMonitor.Weather.Service.Models
+{
+    [PublicAPI]
+    public class WeatherReadingGrouped
+    {
+        public DateTimeOffset Bucket { get; set; }
+
+        public decimal AverageHumidityTemperature { get; set; }
+
+        public decimal AverageHumidity { get; set; }
+
+        public decimal AveragePressureTemperature { get; set; }
+
+        public decimal AveragePressure { get; set; }
+
+        public decimal AverageLightLevel { get; set; }
+    }
+}