Context sensitive item usage from inventory

Allow selecting an item from inventory and show a menu of actions
applicable for that particular item. Some of the entries might
be slightly spoilerish (eg. it'll reveal that you can read T-shirts),
but the improved usability for new players is more than worth it.

Generally known as "item actions", this was first implemented
in AceHack by Alex Smith.

doc/fixes3-7-0.txt

@@ -1540,6 +1540,7 @@ extend farlook's "<mon>, asleep" to "<mon>, can't move (paralyzed or sleeping
 	or busy)" for timed sleep and also "<mon>, meditating" for monster
 	that is waiting for hero to approach
 add body part terminology for spiders; enhance it for cockatrices
+context sensitive item usage menu from inventory, aka "item actions"
 
 
 Platform- and/or Interface-Specific New Features