Wall lights now require light bulbs. (#151)

* Adds light_tube.rsi

Sprites taken from CEV Eris!

* Adds LightBulbComponent

* Wall lights now use light bulbs!

* Light bulb now updates its sprite when it changes.

* Comments the code.

* Adds license and copyright to new sprites

Content.Server/EntryPoint.cs

@@ -86,6 +86,7 @@ namespace Content.Server
             factory.RegisterReference<PowerCellComponent, PowerStorageComponent>();
             factory.Register<PowerDeviceComponent>();
             factory.Register<PowerGeneratorComponent>();
+            factory.Register<LightBulbComponent>();
 
             //Tools
             factory.Register<MultitoolComponent>();