help: Add a screenshot to the combat screen

data/core/help.cfg

@@ -285,7 +285,7 @@ Normally you can undo a unit’s movement, as long as an event with a randomized
     [topic]
         id=combat
         title= _ "Combat"
-        text= _ "Combat in <italic>text='Battle for Wesnoth'</italic> always takes place between units in adjacent hexes. Click on your unit, and click on the enemy you want to attack: your unit will move towards the enemy unit, and when they are next to each other, combat will begin. The attacker and defender alternate strikes until each has used their allotted number of strikes. The attacker chooses one of its weapons to attack with, and the defender retaliates with one of its attacks of the same type. There are two types of attacks: <italic>text='melee'</italic>, which usually involves weapons such as swords, axes or fangs; and <italic>text='ranged'</italic>, which usually involves weapons such as bows, spears and fireballs." + _ "
+        text= "<img>src=help/combat1.png align=left float=yes</img>" + _ "Combat in <italic>text='Battle for Wesnoth'</italic> always takes place between units in adjacent hexes. Click on your unit, and click on the enemy you want to attack: your unit will move towards the enemy unit, and when they are next to each other, combat will begin. The attacker and defender alternate strikes until each has used their allotted number of strikes. The attacker chooses one of its weapons to attack with, and the defender retaliates with one of its attacks of the same type. There are two types of attacks: <italic>text='melee'</italic>, which usually involves weapons such as swords, axes or fangs; and <italic>text='ranged'</italic>, which usually involves weapons such as bows, spears and fireballs." + _ "
 
 <header>text='Order and Number of Strikes'</header>" + _ "