[e494be5] [Duke] Screen "Spasm" when pausing with console

[sinisterseed]

Noticed this a while ago but constantly forgot to point it out.

In certain instances, pausing the game with the console causes a weird "spasm" effect. Oddly it doesn't happen when the pause menu is summoned, only with the console. Cross-checking with EDuke32/Rednukem is useless here since the console does not pause the game in these ports.

Video for demonstration, best seen on the starting elevator on E3M9 Stadium: https://youtu.be/YJAzfYA2W6M

[Rachael]

This is due to the interpolation code, the game sim is paused but it is still trying to move the player view between two points.

[Graf Zahl]

This is something I'm going to address when it's time to refactor the main game loop. Trying to mess around with these variables in the current state will only make things worse.
The view interpolation in some of the games needs a bit of fixing anyway because it only interpolates the position but not the containing sector, resulting in flashes of visual garbage.

[mjr4077au]

Proposed fix submitted in PR #47.