Add API class

- Secure token based on username/password

lib/settings.dart

@@ -0,0 +1,36 @@
+import 'package:flutter/material.dart';
+
+class InvenTreeSettingsWidget extends StatefulWidget {
+  // InvenTree settings view
+
+  @override
+  _InvenTreeSettingsState createState() => _InvenTreeSettingsState();
+
+}
+
+
+class _InvenTreeSettingsState extends State<InvenTreeSettingsWidget> {
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: Text("InvenTree Settings"),
+      ),
+      body: Center(
+        child: ListView(
+          children: <Widget>[
+            ListTile(
+                title: Text("Server Settings"),
+                subtitle: Text("Configure server and login settings"),
+                onTap: _editServerSettings,
+            ),
+          ],
+        )
+      )
+    );
+  }
+
+  void _editServerSettings() {
+
+  }
+}