[webview_flutter] Update README and pubspec (#53)

* Update README
* Update pubspec

Author: seungsoo47

packages/webview_flutter/README.md

@@ -1,4 +1,3 @@
-
 # webview_flutter_tizen
 
 The Tizen implementation of [`webview_flutter`](https://github.com/flutter/plugins/tree/master/packages/webview_flutter).
@@ -7,14 +6,14 @@ The Tizen implementation of [`webview_flutter`](https://github.com/flutter/plugi
 
 This plugin is available on these types of devices:
 
-- Galaxy Watch (running Tizen 5.5 or later)
+- Galaxy Watch or TV (running Tizen 5.5 or later)
 
 ## Usage
 
 ```yaml
 dependencies:
   webview_flutter: ^1.0.6
-  webview_flutter_tizen: ^0.0.1
+  webview_flutter_tizen: ^1.0.0
 ```
 
 To enable tizen implementation, set `WebView.platform = TizenWebView();` in `initState()`.
@@ -45,4 +44,9 @@ class WebViewExampleState extends State<WebViewExample> {
     );
   }
 }
-```
+```
+
+## Limitations
+- This plugin is only supported on **Galaxy Watch and TV** devices running Tizen 5.5 or later.
+- This is an initial webview plugin for Tizen and is implemented based on Tizen Lightweight Web Engine (LWE). If you would like to know detailed specifications that the LWE supports, please refer to the following link :
+https://review.tizen.org/gerrit/gitweb?p=platform/upstream/lightweight-web-engine.git;a=blob;f=docs/Spec.md;h=ecb8f437c5a1facc77d3435e1a8aad6a267f12f3;hb=refs/heads/tizen

packages/webview_flutter/example/pubspec.yaml

@@ -1,29 +1,23 @@
 name: webview_flutter_tizen_example
 description: Demonstrates how to use the webview_flutter_tizen plugin.
 
-# The following line prevents the package from being accidentally published to
-# pub.dev using `pub publish`. This is preferred for private packages.
-publish_to: 'none' # Remove this line if you wish to publish to pub.dev
-
 environment:
   sdk: ">=2.7.0 <3.0.0"
+  flutter: ">=1.20.0 <2.0.0"
 
 dependencies:
   flutter:
     sdk: flutter
-  webview_flutter:
+  webview_flutter: ^1.0.6
   webview_flutter_tizen:
     path: ../
-  cupertino_icons: ^1.0.0
 
 dev_dependencies:
-  flutter_test:
+  flutter_driver:
     sdk: flutter
   integration_test: ^1.0.1
   integration_test_tizen:
     path: ../../integration_test/
 
 flutter:
   uses-material-design: true
-  assets:
-    - assets/sample_audio.ogg

packages/webview_flutter/pubspec.yaml

@@ -4,13 +4,13 @@ homepage: https://github.com/flutter-tizen/plugins
 version: 1.0.0
 
 environment:
-  sdk: ">=2.2.2 <3.0.0"
+  sdk: ">=2.7.0 <3.0.0"
   flutter: ">=1.20.0 <2.0.0"
 
 dependencies:
   flutter:
     sdk: flutter
-  webview_flutter: ^1.0.5
+  webview_flutter: ^1.0.6
 
 dev_dependencies:
   flutter_test: