Initial test of new shader function style

[clayjohn]

Fixes: https://github.com/godotengine/godot-docs/issues/5594

I am looking for feedback on a new style for the shader builtin functions. Previously the descriptions were presented in a table format that made them hard to edit and hard to read.

The new format uses the jsdoc formatting used here

Old Format /tutorials/platform/html5_shell_classref.html)

New Format

[Chaosus]

This looks excellent! :) Maybe the function names should be sorted alphabetically?

[Vennnot]

This would be amazing to have!