[gameplay] Add a flaming status effect to iber champion cavalry

Accepted by: @borg-
Stats by: @wowgetoffyourcellphone
Differential Revision: https://code.wildfiregames.com/D2737
This was SVN commit r24426.

binaries/data/mods/public/art/textures/ui/session/icons/status_effects/textures.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Textures>
+  <File pattern="*" format="dxt5" mipmap="false" filter="box"/>
+</Textures>

binaries/data/mods/public/simulation/data/status_effects/burning.json

@@ -0,0 +1,7 @@
+{
+	"applierTooltip": "This unit causes fire damage.",
+	"code": "Burning",
+	"icon": "burning",
+	"statusName": "Burning",
+	"receiverTooltip": "This unit is burning."
+}

binaries/data/mods/public/simulation/data/template_helpers/damage_types/fire.json

@@ -0,0 +1,6 @@
+{
+	"code": "Fire",
+	"name": "Fire",
+	"description": "Damage caused by burning objects, like a torch or a flaming arrow.",
+	"order": 4
+}

binaries/data/mods/public/simulation/templates/units/iber/champion_cavalry.xml

@@ -2,10 +2,16 @@
 <Entity parent="template_unit_champion_cavalry_javelineer">
   <Attack>
     <Ranged>
-      <Damage>
-        <Pierce>5</Pierce>
-        <Crush>15</Crush>
-      </Damage>
+      <ApplyStatus>
+        <Burning>
+          <Interval>4000</Interval>
+          <Damage>
+            <Fire>1</Fire>
+          </Damage>
+          <Stackability>Stack</Stackability>
+          <Duration>8000</Duration>
+        </Burning>
+      </ApplyStatus>
     </Ranged>
   </Attack>
   <Identity>