Add evcc widget (#1473)

* added all evcc related files

* changed units

* bugfix changed first value to pvPower insted of homePower

* deleted proxy.js

* delted battary label and german translation

* Code style changes to evcc widget

---------

Co-authored-by: shamoon <4887959+shamoon@users.noreply.github.com>

src/widgets/evcc/widget.js

@@ -0,0 +1,14 @@
+import genericProxyHandler from "utils/proxy/handlers/generic";
+
+const widget = {
+  api: "{url}/api/{endpoint}",
+  proxyHandler: genericProxyHandler,
+
+  mappings: {
+    state: {
+      endpoint: "state",
+    }
+  },
+};
+
+export default widget;