Minesweeper: Port to GML compilation

This patch ports minesweeper to GML compilation,
and introduces a few changes made to associated files.

Userland/Games/Minesweeper/MainWidget.gml

@@ -0,0 +1,52 @@
+@Minesweeper::MainWidget {
+    fill_with_background_color: true
+    layout: @GUI::VerticalBoxLayout {
+        spacing: 0
+    }
+
+    @GUI::HorizontalSeparator {
+        name: "separator"
+        fixed_height: 2
+    }
+
+    @GUI::Widget {
+        name: "container"
+        fixed_height: 36
+        layout: @GUI::HorizontalBoxLayout {}
+
+        @GUI::Layout::Spacer {}
+
+        @GUI::ImageWidget {
+            name: "flag_image"
+            bitmap: "/res/graphics/minesweeper/flag.png"
+        }
+
+        @GUI::Label {
+            name: "flag_label"
+            autosize: true
+        }
+
+        @GUI::Layout::Spacer {}
+
+        @GUI::Button {
+            name: "face_button"
+            fixed_size: [36, 36]
+            focus_policy: "TabFocus"
+            button_style: "Coolbar"
+        }
+
+        @GUI::Layout::Spacer {}
+
+        @GUI::ImageWidget {
+            name: "time_image"
+            bitmap: "/res/graphics/minesweeper/timer.png"
+        }
+
+        @GUI::Label {
+            name: "time_label"
+            autosize: true
+        }
+
+        @GUI::Layout::Spacer {}
+    }
+}