Add Alien Invasion map (MT-CTF#293)

alien_invasion/map.conf

@@ -0,0 +1,21 @@
+game_modes = return {"classes","classic","nade_fight"}
+barrier_area = return {pos2={x=229,y=132,z=217},pos1={x=0,y=0,z=0}}
+teams = local _={};_[1]="enabled";_[2]="flag_pos";return {red={pos2={x=0,y=0,z=217},[_[1]]=true,[_[2]]={x=9,y=79,z=109},pos1={x=103,y=132,z=0}},blue={pos2={x=229,y=0,z=0},[_[1]]=true,[_[2]]={x=207,y=79,z=109},pos1={x=103,y=132,z=217}}}
+chests = return {{pos2={x=103,y=131,z=216},amount=50,pos1={x=1,y=78,z=1}},{pos2={x=228,y=131,z=216},amount=50,pos1={x=104,y=78,z=0}}}
+phys_jump = 1
+phys_speed = 1
+size = return {x=229,y=132,z=217}
+map_version = 3
+enabled = true
+name = Alien Invasion
+phys_gravity = 1
+initial_stuff = return {"default:torch 20"}
+author = ScaleRaker, extremyst, MrRar
+hint = Ores are hidden in the base!
+license = CC BY-SA 4.0
+others = Map Testers: HobbitPower, Kat and s20. Screenshot: HobbitPower
+treasures = 
+skybox = FullMoon
+enable_shadows = 0.26
+start_time = 60
+time_speed = 1