Refactored view utils for storing view size, state and position

@min_best_size and @remember_size_pos are replaced by Mixins. Separated Size from Position, allowing for combining Minimalistic with Position storing, without bothering for previous window sites. Also, maximized window state is now being stored as well.
[completed: 84, 83]

mvvm/viewbinding/display.py

@@ -15,15 +15,14 @@ def update_view(self):
         self.field.Show(value == self.show_if_value)
         self.field.GetParent().GetSizer().Layout()
 
-        # resize frame if @min_best_size'd
-        if hasattr(self.field.TopLevelParent, 'MinBestSize'):
+        # resize frame if Minimalistic
+        if hasattr(self.field.TopLevelParent, 'update_minimal_size'):
             # First, invalidate all parents
             parent = self.field.Parent
             while parent:
                 parent.InvalidateBestSize()
                 parent = parent.Parent
-            self.field.TopLevelParent.SetSize(
-                self.field.TopLevelParent.MinBestSize())
+            self.field.TopLevelParent.update_minimal_size()
 
 
 class EnabledBinding(object):