Integrated some of the security records functionality into security HUD. Couple of bugfixes.
Accidentally revoked some other changes
More checks that should have been there in the first place, cleanup.
Missed a sodding "
* prevented empty stacks from being generated on tiles, when merging stacks on floor after crafting them (e.g metal => floor).
Fixes #4775
* various clean-up of unnecessary checks related to stacks
Create the audible_message() proc to replace most instance of " for(var/mob/M in hearers(...)   show_message(..., 2)"

fixing typos and missing emotes in emote lists.
One more hearers replacement.
Location nulling moved to Destroy() proc
Fixing issue where people can't hear their own emotes while inside lockers and the audible messages when also in the dark. Removing object_talk() proc (obsolete).
Replacing two audible_message() by say().
Fixing two small mistakes.
Gives changelings 10 power points, rebalances ability chemical costs, and fixes two bugs and a typo.
whoops, hivemind should cost 2
There will never be more starting head revs than their are heads.

If there's <3 heads, there'll only be as many head revs as heads
Adding say_quote() to library console and supply computers.
...and to ordercomp as well
Undoes slight nerf changes that weren't really needed.
Drops blind sting and both shriek powers to 1 point, drops chitin armor cost by 5
Simplifying audible_message proc by using get_hearers_in_view().
Fixes flash powder only checking for sunglasses protection.
Simplify the flashbang prime() proc a bit.
Late join heads must now be slain to win the round for the head revs

If there are less than 3 head revs and another head joins, a new headrev will be created from from the existing revolutionaries. If there are no revolutionaries that aren't already head revs, the next conversion will be raised to head revolutionary status quickly after conversion.
Merge branch 'master' of https://github.com/tgstation/-tg-station into revheadscaling