Optimizes some functions

[GDNgit]

What Does This PR Do

Optimizes get_area_turfs, get_mobs_in_view, and announcement_help

Why It's Good For The Game

High overtime functions are bad. Getting list information that you won't use is bad. Searching through world contents like 7 times in one tick is really stupid. not storing static information is stupid.

Testing

Tested the announcement_help verb in game. Tested get_area_turfs and ssmapping lists in game. Made sure the game didn't explode on impact from get_mobs_in_view changes.

Changelog

NPFC. Pretty nice lag decreases tho