New scripting: Nodes (something between Scratch and Unreal Blueprints)

Now, player can choose scripting with Nodes instead of Scratch-like blocks.

Nodes are more similar to Unreal's Blueprints. It is less compact at first glance, but give much more flexibility in more complicated programs.

• Output from one node can be connected to inputs of multiple other nodes (which is not possible with Scratch blocks),
• Program can be composed visually for better readability,
• Nodes are potentially not limited to have only one output, which gives more flexibility in development.