Add history endpoint and do some cleanup

Environment/Service/Data/Queries/GetRecentReadings.psql

@@ -0,0 +1,16 @@
+SELECT DISTINCT ON (name)
+    time,
+    name,
+    model,
+    temperature,
+    pressure,
+    humidity,
+    luminance,
+    gas_resistance AS gasResistance,
+    color_temperature AS colorTemperature,
+    air_quality_index AS airQualityIndex
+FROM
+    reading
+ORDER BY
+    name,
+    time DESC