[UPDATE] Arachnophyte

One of the most disappointing monsters currently in the repo is the Arachnophyte. I guess in 2006 when this monster came out alongside Zen Dynamics the standards weren't nearly as high as they are today, so I tried to modernize this monster a bit. Imo the most glaring issues were the sprites and the very low health for such a big monster.

- changed file format from wad to pk3
- improved code
- added code for increased mobility
- re-balanced stats:
    - increased health from 500 to 2000 (the original Zen Dynamics value)
    - increased speed from 6 to 12
    - reduced mass from 5000 to 500
    - reduced height from 100 to 80
- adjusted all sprite offsets
- removed numerous pixel arfifacts and discrepancies between sprite frames
- created brightmaps
- updated GLDEFS
- reduced file size of all graphics and sounds
- improved engine and death sound
- updated INFO and CREDITS


https://drive.google.com/file/d/1WBq26cJWnSUNGTcDB-1TI-_LD25qkWMJ/view?usp=sharing

Updated
Made a small change to its pain state, it played its pain sound twice so I removed one of the A_Pain functions.