Remove more outbox parts, I think these were never even used

indra/newview/skins/default/xui/de/panel_outbox_inventory.xml

@@ -1,2 +0,0 @@
-<?xml version="1.0" encoding="utf-8" standalone="yes"?>
-<outbox_inventory_panel name="inventory_outbox" tool_tip="Legen Sie Artikel hier ab, um sie zum Verkauf in Ihrem Laden vorzubereiten"/>

indra/newview/skins/default/xui/en-us/panel_outbox_inventory.xml

@@ -1,19 +0,0 @@
-<?xml version="1.0" encoding="utf-8" standalone="yes" ?>
-<outbox_inventory_panel
-    name="inventory_outbox"
-    start_folder="Outbox"
-    follows="all" layout="topleft"
-    top="0" left="0" height="165" width="308"
-    top_pad="0"
-    bg_opaque_color="0.169 0.169 0.169 1"
-    bg_alpha_color="0.169 0.169 0.169 1"
-    background_visible="true"
-    border="false"
-    bevel_style="none"
-    show_item_link_overlays="true"
-    tool_tip="Drag and drop items here to prepare them for sale on your storefront"
-    allow_open="false"
-    allow_drop_on_root="false"
-    >
-    <scroll reserve_scroll_corner="false" />
-</outbox_inventory_panel>

indra/newview/skins/default/xui/es/panel_outbox_inventory.xml

@@ -1,3 +0,0 @@
-<?xml version="1.0" encoding="utf-8" standalone="yes" ?>
-<outbox_inventory_panel name="inventory_outbox" tool_tip="Arrastra y suelta aquí los ítems para prepararlos para la venta en el escaparate de tu Tienda">
-</outbox_inventory_panel>