UI enhancements

[tung]

I've made a number of enhancements, mostly related to multipickup and multidrop.

Multipickup (examine)

• Choosing an off-page item changes to that page.
• Show inventory letter if picking up only one item, otherwise print a suitable message.
• Highlight item when its info is shown.
• Capital letters show item info without toggling pickup. Useful for comparisons.

Multidrop

• Choosing an off-page item changes to that page, like the multipickup change.
• Selecting items updates weight and volume. This accounts for weapons and armor too.

I use a loop instead of multiplication to calculate weight and volume for stacks, since that's the way it's done in player.cpp. Is this an oversight, or is it meant to be done this way?

Look around

• Shift+hjklyubn moves around 5 spaces at a time.

Monster list

• Show non-hostile monsters in dark grey. Hostiles (i.e. anything that freaks out run mode) and NPCs keep their usual color.

Other

• Smash and examine directional prompts no longer print "invalid direction" when space/enter are used to dismiss them.
• Use, reassign, consume and wear item prompts no longer print "You don't have item '(space/enter)'!" when these keys are used to dismiss them.

[tung]

To try this out, add my repo as a remote:

git remote add tung git://github.com/tung/Cataclysm.git

Fetch the branch for these enhancements:

git fetch tung ui-changes

Then you can check it out on a local branch, which you can call whatever you like:

git checkout -b ui-changes tung/ui-changes

If you like it, you can merge it in, which automatically closes this pull request. If not, post here and I can change things.