Valkyrie player monster was set to be chaotic even though valk
hero is lawful by default and can also be neutral but not chaotic.
Change it to be lawful. Warrior quest monsters attending leader
were also chaotic; change to lawful to match revised valk. If
hero is a neutral valk then both the player monster and warriors
get changed to neutral at start of game (and stay that way even
if hero changes alignment). The leader defaults to neutral but
gets changed to lawful for lawful valk hero.
Attentdant quest monsters with the healer leader were lawful but
if they gain enough experience they get promoted to healer, so
make them neutral like the latter.
I've added some miscellaneous comments and done a small amount of
reformatting. Comment about alignment changing in bones applies
to all roles that can be played with different alignments, not
just to valkyries. It isn't new; I just thought that it ought to
be mentioned somewhere.
Fixes#521