Some corrections to HUD editor

[Reco1I]

Additions

• Added a per-element restore button.
• Added hit judgments counters for 300s, 100s, 50s and misses.

Changes

• Scale is now normalized for both axis.

Fixes

• Fixed MessageDialog not hiding the message layout if there's no text to display.
• Fixed GameplayLeaderboard not working in Multiplayer.
• Fixed GameplayLeaderboard having zero size when the scores list is empty.
• Fixed toolbar being cropped by the screen when the element position is near-zero in the Y-axis.
• Fixed skin.json being rewritted with no identation.
• Fixed Autoplay mod being enable after exiting HUD editor mode.