Spawn point system.

Hey we can place spawn points on the map now instead of hardcoding them!
Spawn points are simply invisible bare bones entities.

Content.Server/GameObjects/Components/Markers/SpawnPointComponent.cs

@@ -0,0 +1,28 @@
+using System;
+using Content.Shared.GameObjects.Components.Markers;
+using SS14.Shared.GameObjects;
+using SS14.Shared.Serialization;
+using SS14.Shared.ViewVariables;
+
+namespace Content.Server.GameObjects.Components.Markers
+{
+    public sealed class SpawnPointComponent : SharedSpawnPointComponent
+    {
+        private SpawnPointType _spawnType;
+        [ViewVariables]
+        public SpawnPointType SpawnType => _spawnType;
+
+        public override void ExposeData(ObjectSerializer serializer)
+        {
+            base.ExposeData(serializer);
+
+            serializer.DataField(ref _spawnType, "spawn_type", SpawnPointType.Unset);
+        }
+    }
+
+    public enum SpawnPointType
+    {
+        Unset = 0,
+        LateJoin,
+    }
+}