storage upgrade as part of the wizard. fix storage upgrade on kivy.

lib/storage.py

@@ -578,10 +578,17 @@ class WalletStorage(PrintError):
             return True
 
     def get_action(self):
-        action = run_hook('get_action', self)
-        if action:
-            return action
-        if not self.file_exists():
+        if self.file_exists():
+            action = run_hook('get_action', self)
+            if action and self.requires_upgrade():
+                raise WalletFileException(_('Incomplete wallet files cannot be upgraded.'))
+            elif self.requires_upgrade():
+                return 'upgrade_storage'
+            elif action:
+                return action
+            else:
+                return None
+        else:
             return 'new'
 
     def get_seed_version(self):