Added entity map for getting entities by absolute tile

Conflicts:
	CorsixTH/Lua/entities/object.lua
	CorsixTH/Lua/world.lua

Conflicts:
	CorsixTH/Lua/app.lua
	CorsixTH/Lua/world.lua
Contagious patients can infect other patients in adjacent squares
Determine when epidemic is ready to reveal
Sending of initial fax and function stubs for fax choices

Conflicts:
	CorsixTH/Lua/dialogs/fullscreen/fax.lua
Declare epidemic logic added for fax choice
Cover up logic for fax option and countdown option added
Application of cover up result including evacuation
Added inspector who now applies to outcome of coverup when arrives
Additional checks for epidemic win conditions

Conflicts:
	CorsixTH/Lua/entities/patient.lua
	CorsixTH/Lua/humanoid_actions/die.lua
Added vaccination mode click behaviour

Conflicts:
	CorsixTH/Lua/dialogs/watch.lua
	CorsixTH/Lua/entities/patient.lua
	CorsixTH/Lua/game_ui.lua
	CorsixTH/Lua/ui.lua

Conflicts:
	CorsixTH/Lua/dialogs/watch.lua
	CorsixTH/Lua/entities/patient.lua
	CorsixTH/Lua/game_ui.lua
	CorsixTH/Lua/ui.lua
Selection and management of vaccination candidate
Vaccination candidate calls for vaccination and answered by nurse

Conflicts:
	CorsixTH/Lua/calls_dispatcher.lua
Nurse walking to perform vaccination action
Move vaccination to action performed after walking to vaccination candidate
Added interrupt handling to vaccination actions
Mood priority and dynamic info adjusted - new string added
Added adviser messages if epidemic status meets certain conditions
Added infrastructure for supporting multiple epidemics

Conflicts:
	CorsixTH/Lua/hospital.lua
Add the actual logic to fully support multiple epidemics
Ensure fax arrival for epidemic and emergency doesn't interfere with respective events