Godot rain shader

This project adds wetness and rain effect to material. Work in progress.

You can on_off noise generated puddles and add puddles texture. Realized roofs.

So, this work based on:

1. youtube lessons of Ben Cloward https://www.youtube.com/watch?v=fYGOZYST-oQ&list=PL78XDi0TS4lHpIHseomZCPRm_NkyUMkPs

2. streaks: https:/deepspacebanana.github.io/blog/shader/art/unreal engine/Rainy-Surface-Shader-Part-1

3. wet albedo: https://seblagarde.wordpress.com/2013/04/14/water-drop-3b-physically-based-wet-surfaces/