Show item info by hovering cursor over item.
Deselect item only if unload actually happened.
Close inventory screen by its hotkey.
Merge branch 'ui_inventoryhover' of https://github.com/dtrushn/OpenXcom

Conflicts:
	src/Battlescape/Inventory.cpp
	src/Battlescape/Inventory.h
	src/Battlescape/InventoryState.cpp