Implement animated flipbook style textures for weapon projectiles.

[lhog]

Use animParams1, animParams2, animParams3, animParams4 in a weaponDef to animate texture1, texture2, texture3, texture4 respectively or animParams to animate all of them the same way.

Implements #1565

[MaDDoXbr]

The final effect of the 'flipbook texture1' can be seen in the attached mp4.
https://github.com/user-attachments/assets/09a103cd-f1b5-41c9-bc9e-ada39a83c927

As a reference, that's what I added to the shown weapondef:

animParams1 = "4 1 8",  --xres = 4, yres = 1, animLength = 8
stages = 1,                      -- to get rid of the "trail replicas" shown behind the cannon projectile 

• animLength defines the time in game frames during which the whole flipbook sequence is played from start to finish, if it's positive, then animation restarts from start after; if it's negative the animation "ping pongs".