Feature Request: Adding new water effects

[Adngel]

I add issue here to don't forget it in the future.

• Update Water Splash into something more beautiful
• Add function for EmitBubbles(pos, density) (That reacts to the surface detection).
• MakeExplosion(pos, size, shockwave) (Right now, if triggered in an underwater room, it does the same effect than in dry rooms).
• EmitCurrent(pos, rot, speed/intensity, length) (Show small particules that follows a current stream.
• EmitClassicWaterfallSplashes. (like the ones used in TR1 and TR2).

Requests are for lua API functions and nodes.