scroll usage; also spell of ID (trunk only)

scroll usage; also spell of ID (trunk only)

     Make a not-very-robust fix for the report from <email deleted> about
being told a scoll disappears as you read it, then for the case of cursed
remove curse being told that the scroll disintegrates.  He missed similar
case for scroll of fire erupting into flames after it had disappeared.
This suppresses the "disappears" part of the scroll reading message for
those two cases, but won't be very reliable if other scroll messages
referring to the scroll itself get introduced in the future.  [Several
paths through scroll of fire won't report that it burns, and now it doesn't
give the disappears message any more.  I don't think that's worth worrying
about; the scroll leaving inventory after burning up is implicit.]

     Also cut down on redundant feedback for several scrolls (genocide,
charging, identify, stinking cloud) that start off by informing the player
what they are.  That's only needed when the the player doesn't already
know the type of scroll.  I've always felt it silly to be told that I've
"found a scroll of genocide" when I'm intentionally reading a known scroll
of genocide.  All these types of scroll give a subsequent prompt which
makes them recongizable if you somehow manage to choose the wrong object
when picking the one to read.

    Lastly, make spell of identify behave like ordinary uncursed scroll of
identify by default instead of ususally ID'ing multiple items.  Now you'll
need to be skilled or better in divination spells skill in order to get the
blessed scroll effect out of it.  And give some feedback if the spell is
cast when not carrying any inventory; it was just silently moving on to the
user's next command in that case.