Proper mirror PR for the disease refactor because I fucked up the first one. (#2026)

* Revert "im a dumbass and didn't see the .rej files Revert "[MIRROR] Disease Refactor" (#2025)"

This reverts commit 44742cb115.

* Delete shuttle_loan.dm.rej

* Delete life.dm.rej

* Update life.dm

* Delete life.dm.rej

* compile

code/modules/events/disease_outbreak.dm

@@ -27,11 +27,17 @@
 			continue
 		if(T.z != ZLEVEL_STATION)
 			continue
-		var/foundAlready = 0	// don't infect someone that already has the virus
-		for(var/datum/disease/D in H.viruses)
-			foundAlready = 1
+		if(!H.client)
+			continue
+		if(H.stat == DEAD)
+			continue
+		if(VIRUSIMMUNE in H.dna.species.species_traits) //Don't pick someone who's virus immune, only for it to not do anything.
+			continue
+		var/foundAlready = FALSE	// don't infect someone that already has a disease
+		for(var/thing in H.viruses)
+			foundAlready = TRUE
 			break
-		if(H.stat == DEAD || foundAlready)
+		if(foundAlready)
 			continue
 
 		var/datum/disease/D
@@ -45,6 +51,6 @@
 			DS.strain_data["SE"] = H.dna.struc_enzymes
 		else
 			D = new virus_type()
-		D.carrier = 1
+		D.carrier = TRUE
 		H.AddDisease(D)
 		break