ZDoom fixes, also improvements

- Fixed building on (G)ZDoom due to conflicts with sqrt() and strcmp() due to ZDoom already having these functions
- Wrote a batch file to compile pk3 and pk7 files instead of doing it manually
- Re-did your invulnerability script to not be redundant with it's checking and to condense it as well as make it a bit more flexible if you want to change the timing of the effects and the total time it'll last
- Added the case pairs constants for the DECORATE script in both ACS and DECORATE and implemented them into the Player and Sword actors