Settings split according to chart

routes/api.js
   - check type of sensor
   - translate error message

app.js
   - debug = false at i18n

public/javascripts/chart_utilities.js
   - setter/getter for current Tab

public/javascripts/global.js
   - settings dialog completely rearranged
   - if only sensorid is given, check type

routes/index.js
   - set language to global variable

views/index.pug
   - reaggange settings dialog
   - translate 'Error'

views/layout.pug
   - load new datepicker (vanillajs-datepicker)

public/javascripts/map.js
   - fetching from server refactored to function
   - reenable tabs after leaving map

charts/preparecharts
   - typo

public/javascripts/showcharts.js
   - loadAll extended to  load also live and map

public/stylesheets/style.sass
   - a few changes for settinds dialog

locales/[de|en]
   - added a few words

charts/utilities.js
   - setter and getter for language

public/javascripts/chart_utilities.js

@@ -15,7 +15,7 @@ let stucols = 1;                        // Anzeige nur Balken (StundenMittel)
 
 export const noise_ymin = 30;                    // lowest value on y-axis for noise
 export const noise_ymax = 120;                   // highest value on y-axis for noise
-let activeTab = 0;                      // active TAB number
+let activeTab = 'maptab';                      // active TAB ID
 export let peaklim = 70;                       // threshold for peak count
 
 export const url = '/api'
@@ -197,3 +197,18 @@ export const showTabs = () => {
     document.querySelector('#navi').style.display = 'block'
 }
 
+export const setCurrentTab = (tab) => {
+    activeTab = tab
+}
+
+export const getCurrentTab = () => {
+    return activeTab
+}
+
+export const fetchfromserver = async (url) => {
+    const ret = await fetch(url)
+        .catch(e => {
+            showError(e)
+        });
+    return await ret.json()
+}