Adds a more general way to handle gameplay tips, and adds
a boolean option "tips", which can be used to disable all
tips. Adds a helpful longer message when the game goes
into the "farlook" mode.
Also adds a lua binding to easily show multi-line text
in a menu window.
Breaks save compat.
Adds possible callbacks for "start_new_game", "restore_old_game",
"moveloop_turn", and "game_exit" which when defined, will be called
from core code at the appropriate time.
Adds lua hooks for dump_fmtstr (only if DUMPLOG), dnum_name, u.moves,
u.uhave_amulet, and u.depth.
