Integrate Jetryl's shortsword icon.

Among other things, this replaces the lame-looking shortsword in
Liberty.  There probably ouyght to be a special Orcish variant for the
Orcish Crossbownan and Slurbow.

data/campaigns/Descent_Into_Darkness/units/apprentice-mage.cfg

@@ -22,7 +22,7 @@
     [attack]
         name=short-sword
         description=_ "short sword"
-        icon=attacks/sword-human.png
+        icon=attacks/shortsword.png
         type=blade
         range=melee
         damage=4

data/campaigns/Descent_Into_Darkness/units/apprentice-necromancer.cfg

@@ -21,7 +21,7 @@
     [attack]
         name=short-sword
         description=_ "short sword"
-        icon=attacks/sword-human.png
+        icon=attacks/shortsword.png
         type=blade
         range=melee
         damage=6

data/campaigns/Descent_Into_Darkness/units/dark-mage.cfg

@@ -23,7 +23,7 @@ Special Notes:"+{SPECIAL_NOTES_MAGICAL}
     [attack]
         name=short sword
         description=_ "short sword"
-        icon=attacks/sword-human.png
+        icon=attacks/shortsword.png
         type=blade
         range=melee
         damage=5

data/campaigns/Liberty/units/Rogue_Mage.cfg

@@ -28,7 +28,7 @@
     [attack]
         name=short sword
         description= _ "short sword"
-        icon=attacks/sword-human.png
+        icon=attacks/shortsword.png
         type=blade
         range=melee
         damage=5

data/campaigns/Liberty/units/Shadow_Mage.cfg

@@ -31,7 +31,7 @@
     [attack]
         name=short sword
         description= _ "short sword"
-        icon=attacks/sword-human.png
+        icon=attacks/shortsword.png
         type=blade
         range=melee
         [specials]

data/core/units/humans/Loyalist_Bowman.cfg

@@ -21,9 +21,9 @@
     unit_description= _ "The use of archery in shooting something other than game was seen from its inception, and archers have been indispensable in warfare since time immemorial. Usually of humble origins, hailing from the peasantry or woodsmen, bowmen are competent with both a bow and a short sword, and are very common on the battlefield."
     die_sound={SOUND_LIST:HUMAN_DIE}
     [attack]
-        name=sword
-        description=_"sword"
-        icon=attacks/sword-human.png
+        name=short sword
+        description=_"short sword"
+        icon=attacks/shortsword.png
         type=blade
         range=melee
         damage=6

data/core/units/orcs/Crossbowman.cfg

@@ -22,7 +22,7 @@
     [attack]
         name=short sword
         description=_"short sword"
-        icon=attacks/sword-orcish.png
+        icon=attacks/shortsword.png
         type=blade
         range=melee
         damage=4

data/core/units/orcs/Slurbow.cfg

@@ -25,7 +25,7 @@ Orcs prize any such weapons they can manage to plunder, and they invariably end
     [attack]
         name=short sword
         description=_"short sword"
-        icon=attacks/sword-orcish.png
+        icon=attacks/shortsword.png
         type=blade
         range=melee
         damage=8