Tutorial level

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

Breaks save and bones compat.

doc/Guidebook.tex

@@ -4979,6 +4979,10 @@ command.  Persistent.
 % Display intended path during each step of travel (default off).
 % Debug mode only.
 %.lp
+\item[\ib{tutorial}]
+Play a tutorial level at the start of the game.
+Setting this option on or off in the config file will skip the query.
+%.lp
 \item[\ib{verbose}]
 Provide more commentary during the game (default on).  Persistent.
 %.lp