feat: add error screen to handle network and other errors

lib/widgets/error_reload.dart

@@ -0,0 +1,42 @@
+import 'package:flutter/material.dart';
+import 'link.dart';
+
+class ErrorReload extends StatelessWidget {
+  final String text;
+  final Function reload;
+
+  ErrorReload({@required this.text, @required this.reload});
+
+  @override
+  Widget build(BuildContext context) {
+    return Container(
+      padding: EdgeInsets.symmetric(vertical: 30, horizontal: 20),
+      child: Column(
+        children: <Widget>[
+          Text(
+            'Woops, something bad happened. Error message:',
+            style: TextStyle(fontSize: 16),
+          ),
+          Padding(padding: EdgeInsets.only(top: 10)),
+          Text(
+            text,
+            style: TextStyle(
+              fontSize: 14,
+              fontWeight: FontWeight.w300,
+              color: Colors.redAccent,
+            ),
+          ),
+          Padding(padding: EdgeInsets.only(top: 10)),
+          Link(
+            child: Text(
+              'Reload',
+              style: TextStyle(fontSize: 20, color: Colors.blueAccent),
+            ),
+            beforeRedirect: reload,
+            material: false,
+          ),
+        ],
+      ),
+    );
+  }
+}