sg for SteamGifts

Invalid date

- Hiding games was impossible for some games, which has been fixed.
- The 'Enter' button no longer shows up for closed giveaways, such as in your 'Entered Giveaways' list.
- The app would sometimes think you're logged in, even though your session expired. It'll now log you out, instead of leaving you logged in.
- Layout issues have been fixed.
- Some minor crashes have been fixed.