Simplified algorithm and process of programming nodes

I removed tokens. This enables slightly easier and more open programming of nodes. Along with that, I changed the algorithm executing the script, so that now data connections are always forward updated on change and not backward updated on request. This makes execution flows slower but pure data flows faster and simpler. I would like to create some live video and audio processing nodes in this version to show what it is capable of. The biggest issue is currently performance when combining dataflows with execution nodes.