Close out old legacy versions from status notifications

[Lineflyer]

As mentioned in cgeo/cgeo#6334

We have to close out the current legacy version (and older versions) from the notification system as otherwise those will be informed about the upcoming new legacy versions which are not suitable for those devices.

So devices running version code 20140342 or earlier should not receive an information once we reuse the legacy environment for the new legacy version(s).

[Lineflyer]

@samueltardieu
If you find time, fixing this would be helpful once the new legacy is out.
Up to then I will not trigger any notification regarding legacy update, to avoid informing users with old legacy wrongly.

[Lineflyer]

Edit:
I could not resist:
[20:03] I think I will trigger the legacy notification nontheless. Users of old legacy will see the update notification, but Google Play will show it as not compatible. I am keen to see user amounts for legacy on status.cgeo.org