Slate HUD

First release.

• Parts of the game's HUD in Slate's look while the Slate style is on: the hotbar, the status effects and the held item's name, each where the game has it.
• The experience bar and a mount's jump bar are the game's own, with only their background recoloured to Slate's tones.
• Hearts, armour, hunger, air and a mount's hearts stay the game's icons. Each can be switched to a bar in Slate's look in the settings; those are off unless you switch them on.
• Every part has a switch of its own, and there is one for the whole HUD (Options > Interface > HUD with Slate Config). A part that is off is drawn by the game.
• A part another mod draws itself is left to that mod: Better Inventory's hotbar, and with the bars on, the hearts of Overflowing Bars, Colorful Hearts and Classic Bar.

Slate modules need the Slate Core of their own version: update all of them together.