-tg- disease1

Wee! Readds Disease1, kills off disease2, and finally removes poop.dmi
(fucking piece of shit)

Needs WAY more testing, most of which I don't know how to do yet, because
I've never used this system. Fun!

Changes:
 - Virus2 has been removed completely.
  - Some symptoms have not been readded. Aka, none of them have been
    readded, I just wanted to get this shit ported.
  - Virology has been updated slightly to mirror -tg-'s boxstation, as the
    virus2 machines are gone.
 - Welcome back, disease1
  - The centrifuge, vials, splicer, analyzer, growerthing, have all been
    replaced by the PanD.E.M.I.C. 2220
  - No symptoms have been completely removed; However, vision symptoms
    have been disabled pending byond 510, and genetics symptoms have been
    disabled until "when I figure out how to fix them".
  - Advanced Mutation Toxin now uses a disease, which turns people from
    species, to slime person, to slime. Slime people are instantly turned
    to a slime.
  - Diseased touch now give people appendicitis. Yes, they VANT YOUR...
    appendix.
  - Virology now has a fridge with the following in it:
    - Antiviral Syringes
    - 1 Rhinovirus culture
    - 1 Flu culture
    - 1 Bottle of Mutagen
    - 1 Bottle of Plasma
    - 1 Bottle of Synaptizine
  - A few more things, which I can't remember and can't look at while writing
    this commit. Sometimes, git hurts.

TODO:
 - Test more shit and figure out how the PanD.E.M.I.C. works/is supposed to
   work.
 - Fix genetics symptoms.
 - Give vampires a less shitty diseased touch.
 - Add appendicitis event.
 -

code/defines/procs/AStar.dm

@@ -70,6 +70,10 @@ Actual Adjacent procs :
 
 //the actual algorithm
 /proc/AStar(start, end, atom, dist, maxnodes, maxnodedepth = 30, mintargetdist, adjacent = /turf/proc/reachableAdjacentTurfs, id=null, turf/exclude=null, simulated_only = 1)
+	//sanitation
+	start = get_turf(start) //IF YOU WANT A FUCKING TURF TRY CASTING IT BEFORE THE FUCKING FIRST CALL
+	if(!start)
+		return 0
 
 	if(maxnodes)
 		//if start turf is farther than maxnodes from end turf, no need to do anything
@@ -82,10 +86,6 @@ Actual Adjacent procs :
 	var/list/path = null //the returned path, if any
 	var/PathNode/cur //current processed turf
 
-	//sanitation
-	start = get_turf(start)
-	if(!start)
-		return 0
 
 	//initialization
 	open.Insert(new /PathNode(start,null,0,call(start,dist)(end),0))