Symbinode v0.3.1

Hi. After a long summer, a bunch of technical fixes, and a little rest, we finally finished working on this update. 

Overall, there were quite a few changes inside. All of them resulted in noticeable performance improvements. Below are the most important changes:

• Material view: significantly improved performance and responsiveness (especially noticeable in 4k).
• Node editor: optimized operations of interaction with nodes. Significantly improved performance.
• Optimized interface as a whole, elements are redrawn less.
• Magnetic connection when dragging a node pin.
• Ability to insert a node into a connection.
• Ability to remove a node from a connection without breaking it.
  ( Ctrl+Delete )
• Added possibility to change node bit depth to 16 bits.
• Fixed small artifacts on the texure border

Next, we begin work on v0.4, which will add the next pack of nodes. Thank you to everyone who visits our program even when there is no update, to everyone who is waiting for an update. We are working as much as we can, thank you for understanding. 

If you want to help the project or have feedback, please feel free to leave comments.