Render the loading screen sooner and more often. Closes #2606.
At the beginning the loading screen is rendered at 0% twice to clear front & backbuffer properly. This mostly prevents the black flash at the beginning. What remains is one short period of black screen, but that happens with every fullscreen application.
Remove the !Graphics()->IsIdle() check, which was causing few frames to be rendered and sometimes prevented the initial rendering. This will slightly increase load...
Add a feature to the map editor so that you could place a "tee" into the map and then see which spawn the enemy would get depending on the position of the placed tee.
This would help in quickly testing spawns for potential abuse in game.
Could be visualized by drawing lines from the tee to all the enemy spawns, with the spawn that would be chosen highlighted.
The tee could then be dragged around live with the lines updating in real time.
![distance1](https://user-images.githubuser...