add setting to change temperature between C and F.

fixes #175

webapp/frontend/src/app/shared/shared.module.ts

@@ -1,13 +1,15 @@
 import { NgModule } from '@angular/core';
 import { CommonModule } from '@angular/common';
 import { FormsModule, ReactiveFormsModule } from '@angular/forms';
-import {FileSizePipe} from "./file-size.pipe";
+import {FileSizePipe} from './file-size.pipe';
 import { DeviceSortPipe } from './device-sort.pipe';
+import { TemperaturePipe } from './temperature.pipe';
 
 @NgModule({
     declarations: [
         FileSizePipe,
-        DeviceSortPipe
+        DeviceSortPipe,
+        TemperaturePipe
     ],
     imports: [
         CommonModule,
@@ -19,7 +21,8 @@ import { DeviceSortPipe } from './device-sort.pipe';
         FormsModule,
         ReactiveFormsModule,
         FileSizePipe,
-        DeviceSortPipe
+        DeviceSortPipe,
+        TemperaturePipe
     ]
 })
 export class SharedModule

webapp/frontend/src/app/shared/temperature.pipe.spec.ts

@@ -0,0 +1,8 @@
+import { TemperaturePipe } from './temperature.pipe';
+
+describe('TemperaturePipe', () => {
+  it('create an instance', () => {
+    const pipe = new TemperaturePipe();
+    expect(pipe).toBeTruthy();
+  });
+});

webapp/frontend/src/app/shared/temperature.pipe.ts

@@ -0,0 +1,34 @@
+import { Pipe, PipeTransform } from '@angular/core';
+
+@Pipe({
+  name: 'temperature'
+})
+export class TemperaturePipe implements PipeTransform {
+    static celsiusToFahrenheit(celsiusTemp: number): number {
+        return celsiusTemp * 9.0 / 5.0 + 32;
+    }
+    static formatTemperature(celsiusTemp: number, unit: string, includeUnits: boolean): unknown {
+        let convertedTemp
+        let convertedUnitSuffix
+        switch (unit) {
+            case 'celsius':
+                convertedTemp = celsiusTemp
+                convertedUnitSuffix = '°C'
+                break
+            case 'fahrenheit':
+                convertedTemp = TemperaturePipe.celsiusToFahrenheit(celsiusTemp)
+                convertedUnitSuffix = '°F'
+                break
+        }
+        if(includeUnits){
+            return convertedTemp + convertedUnitSuffix
+        } else {
+            return convertedTemp
+        }
+    }
+
+  transform(celsiusTemp: number, unit = 'celsius', includeUnits = false): unknown {
+        return TemperaturePipe.formatTemperature(celsiusTemp, unit, includeUnits)
+  }
+
+}