fix(window): save maximized state

Save the window state when the window is maximized so it's remembered until next time the window
opens.

fix #475

src/main/helpers/window.js

@@ -67,7 +67,7 @@ export default function (name, options) {
   };
 
   var saveState = function () {
-    if (!win.isMinimized() && !win.isMaximized()) {
+    if (!win.isMinimized()) {
       Object.assign(state, getCurrentPosition());
     }
     userDataDir.write(stateStoreFile, state, { atomic: true });