Fixed: playerid for specialblocks was index

The id of the player who placed a special block is now not the z-index
of the block but instead the player id.
Don't need to check if sci-fi block

The server will only send messages to the "br" event if it qualifies.
Adding forwards compatibility for note blocks

Just just in case, if a note-block isn't defined then warn the user that
it doesn't exist but still place it on the map as a regular block.
Documentating possible room bug
Level is used