croupier: Add Better Splash Screen

The splash screen was blatantly copied from
https://vanadium-review.googlesource.com/#/c/18335
(The Syncslides Flutter Splash screen)

Change-Id: I39b9f674a5f2708f006128d30abb19b769442326
diff --git a/images/splash/background.png b/images/splash/background.png
new file mode 100644
index 0000000..4812cbb
--- /dev/null
+++ b/images/splash/background.png
Binary files differ
diff --git a/images/splash/flutter.png b/images/splash/flutter.png
new file mode 100644
index 0000000..0f468b6
--- /dev/null
+++ b/images/splash/flutter.png
Binary files differ
diff --git a/images/splash/vanadium.png b/images/splash/vanadium.png
new file mode 100644
index 0000000..6da0b2a
--- /dev/null
+++ b/images/splash/vanadium.png
Binary files differ
diff --git a/lib/components/main_route.dart b/lib/components/main_route.dart
index 4cbcf4d..509f5d9 100644
--- a/lib/components/main_route.dart
+++ b/lib/components/main_route.dart
@@ -50,9 +50,22 @@
 
   // TODO(alexfandrianto): Can we do better than this?
   Widget _buildSplashScreen() {
-    return new Container(
-        decoration: style.Box.liveNow,
-        child: new Text("Loading Croupier...", style: style.Text.titleStyle));
+    var stack = new Stack([
+      new AssetImage(name: 'images/splash/background.png', fit: ImageFit.cover),
+      new Row([
+        new AssetImage(
+            name: 'images/splash/flutter.png', width: style.Size.splashLogo),
+        new AssetImage(
+            name: 'images/splash/vanadium.png', width: style.Size.splashLogo)
+      ], justifyContent: FlexJustifyContent.center),
+      new Container(
+          child: new Row(
+              [new Text('Loading Croupier...', style: style.Text.splash)],
+              alignItems: FlexAlignItems.end,
+              justifyContent: FlexJustifyContent.center),
+          padding: style.Spacing.normalPadding)
+    ]);
+    return stack;
   }
 
   void _showDrawer() {
diff --git a/lib/styles/common.dart b/lib/styles/common.dart
index 73e731b..b2ee9ed 100644
--- a/lib/styles/common.dart
+++ b/lib/styles/common.dart
@@ -19,22 +19,16 @@
   static final TextStyle largeStyle = new TextStyle(fontSize: 24.0);
   static final TextStyle largeRedStyle =
       new TextStyle(fontSize: 24.0, color: errorTextColor);
+  static final TextStyle splash =
+      new TextStyle(fontSize: 16.0, color: Colors.white);
 }
 
 class Size {
-  static const double thumbnailWidth = 250.0;
-  static const double listHeight = 150.0;
-  static const double thumbnailNavHeight = 150.0;
-  static const double thumbnailNavWidth = 267.0;
+  static const double splashLogo = 75.0;
 }
 
 class Spacing {
-  static final EdgeDims extraSmallPadding = new EdgeDims.all(2.0);
-  static final EdgeDims smallPadding = new EdgeDims.all(5.0);
   static final EdgeDims normalPadding = new EdgeDims.all(10.0);
-  static final EdgeDims normalMargin = new EdgeDims.all(2.0);
-  static final EdgeDims listItemMargin = new EdgeDims.TRBL(3.0, 6.0, 0.0, 6.0);
-  static final EdgeDims thumbnailNavMargin = new EdgeDims.all(3.0);
 }
 
 class Box {
diff --git a/manifest.yaml b/manifest.yaml
index 07fe25a..f9e8c92 100644
--- a/manifest.yaml
+++ b/manifest.yaml
@@ -231,3 +231,6 @@
   - images/avatars/player1.jpeg
   - images/avatars/player2.jpeg
   - images/avatars/player3.jpeg
+  - images/splash/background.png
+  - images/splash/flutter.png
+  - images/splash/vanadium.png