Merge branch 'clhp_map' into 'main'

Choropleth map implementation

See merge request !3

server/sql_db/schema.sql

@@ -16,6 +16,8 @@ CREATE TABLE Measurement (
     SensorID INT NOT NULL,
     TimeMeasured DATETIME NOT NULL,
     WaterBodyName TEXT NOT NULL,
+    CenterLat FLOAT NOT NULL,
+    CenterLon FLOAT NOT NULL,
     WholeAverageThickness FLOAT NOT NULL,
     FOREIGN KEY (SensorID) REFERENCES Sensor(SensorID),
     FOREIGN KEY (WaterBodyName) REFERENCES BodyOfWater(Name)