complete widget submodule refactory

src/browser/main/tab/label/pin/widget.rs

@@ -0,0 +1,20 @@
+pub struct Pin {
+    gtk: gtk::Image,
+}
+
+impl Pin {
+    // Construct
+    pub fn new() -> Pin {
+        let gtk = gtk::Image::builder()
+            .icon_name("view-pin-symbolic")
+            .visible(false) //@TODO
+            .build();
+
+        Self { gtk }
+    }
+
+    // Getters
+    pub fn gtk(&self) -> &gtk::Image {
+        &self.gtk
+    }
+}