kivy wizard: add explicit warnings at seed creation

electrum/gui/kivy/uix/dialogs/installwizard.py

@@ -834,7 +834,12 @@ class ChoiceLineDialog(WizardChoiceDialog):
 
 class ShowSeedDialog(WizardDialog):
     seed_text = StringProperty('')
-    message = _("If you forget your password or lose your device, your seed phrase will be the only way to recover your funds.")
+    message = (_("Write your seed phrase down on paper.") + " " +
+               _("The seed phrase will allow you to recover your wallet in case you forget your password or lose your device.") + "\n\n" +
+               _("WARNING") + ":\n" +
+               "- " + _("Never disclose your seed.") + "\n" +
+               "- " + _("Never type it on a website.") + "\n" +
+               "- " + _("Do not store it electronically."))
 
     def __init__(self, wizard, **kwargs):
         super(ShowSeedDialog, self).__init__(wizard, **kwargs)