Display app improvements

- Add summary page
- Use common time range component

Display/src/app/models/time-span.ts

@@ -0,0 +1,5 @@
+export enum TimeSpan {
+    Last24Hours,
+    Day,
+    Custom
+}

Display/src/app/models/weather/weather-aggregates.ts

@@ -0,0 +1,15 @@
+export interface WeatherAggregates {
+    humidity: WeatherAggregate;
+    temperature: WeatherAggregate;
+    pressure: WeatherAggregate;
+    light: WeatherAggregate;
+    windSpeed: WeatherAggregate;
+    windDirectionAverage: number;
+    rainTotal: number;
+}
+
+export interface WeatherAggregate {
+    min: number;
+    max: number;
+    average: number;
+}