Fix the advanced inventory.

Fixes #9199 - needed proper comparison. I copied the insightful comment from https://github.com/CleverRaven/Cataclysm-DDA/pull/9180#issuecomment-56475598 there to replace the TODO, hope that's ok.

Fixes #9197 - the label is shown below the vehicle name. Name, label and the name of the square (e.g. north, south, inventory) are truncated now.

And it also fixes the bug that came up in the forum:  http://smf.cataclysmdda.com/index.php?topic=7865.msg180239#msg180239 where the maximal amount of items that can be put into something was wrong.

Thanks to KA101 for pointing out the problem with the key bindings. While I wrote that, I had changed the location of the panes to use enums (`aim_location`) instead of plain integers and suddenly the key bindings were wrong. I looked them up in the default key bindings file, were they had proper names (e.g. action "ITEMS_NW" had the name "Select items @ North-West"). Following this the default bindings did not match either the display (the 3x3 table in the corners), nor the number pad, nor the entries in the popup menu so I just had correct that.

My apologies for the inconvenience.