Implemented cascading station deletion

ref #67

src/errors/ScanStationErrors.ts

@@ -22,4 +22,15 @@ export class ScanStationIdsNotMatchingError extends NotAcceptableError {
 
 	@IsString()
 	message = "The ids don't match! \n And if you wanted to change a scan station's id: This isn't allowed!"
-}
+}
+
+/**
+ * Error to throw when a station still has scans associated.
+ */
+export class ScanStationHasScansError extends NotAcceptableError {
+	@IsString()
+	name = "ScanStationHasScansError"
+
+	@IsString()
+	message = "This station still has scans associated with it. \n If you want to delete this station with all it's scans add `?force` to your query."
+}