Tutorial level

Add a tutorial level to teach commands to new players.
Very much a WIP.

Breaks save and bones compat.

sys/windows/vs/files.props

@@ -127,6 +127,7 @@
     <Luafiles Include = "tower1.lua"/>
     <Luafiles Include = "tower2.lua"/>
     <Luafiles Include = "tower3.lua"/>
+    <Luafiles Include = "tut-1.lua"/>
     <Luafiles Include = "Val-fila.lua"/>
     <Luafiles Include = "Val-filb.lua"/>
     <Luafiles Include = "Val-goal.lua"/>