Add shared_preferences plugin

Author: CoderJava

pubspec.lock

@@ -659,7 +659,7 @@ packages:
     source: hosted
     version: "1.2.0"
   shared_preferences:
-    dependency: transitive
+    dependency: "direct main"
     description:
       name: shared_preferences
       url: "https://pub.dartlang.org"

pubspec.yaml

@@ -65,6 +65,10 @@ dependencies:
   # Scalable Vector Graphics 1.1 files.
   flutter_svg: ^1.1.0
 
+  # Flutter plugin for reading and writing simple key-value pairs. Wraps NSUserDefaults on iOS
+  # and SharedPreferences on Android.
+  shared_preferences: ^2.0.15
+
 dev_dependencies:
   flutter_test:
     sdk: flutter