Add soccer tips set

data/tips.xml

@@ -23,4 +23,13 @@
         <tip text="Basketballs can be destroyed using precise backward shots with a bowling ball, cake or plunger."/>
         <tip text="Try to avoid crashing into other karts unless you want to throw them off the track."/>
     </tipset>
+    <tipset id="soccer">
+        <tip text="You can use bowling balls to push and block the ball."/>
+        <tip text="In soccer, always work as a team for good results."/>
+        <tip text="If you miss the ball and an opponent is approaching, try hitting them with a powerup or block their way."/>
+        <tip text="Good rotation of positions (attack and defense) is essential."/>
+        <tip text="Make sure to store at least 2 big cans worth of nitro."/>
+        <tip text="Never use the three bowling balls all at the same time."/>
+        <tip text="Don't get in the way of a teammate carrying the ball, though you can try to hit opponents attempting to stop them from scoring."/>
+    </tipset>
 </tips>

src/states_screens/race_result_gui.cpp

@@ -147,7 +147,10 @@ void RaceResultGUI::init()
 #ifndef SERVER_ONLY
     if (!human_win && !NetworkConfig::get()->isNetworking())
     {
-        core::stringw tip = TipsManager::get()->getTip("race");
+        std::string tipset = "race";
+        if (RaceManager::get()->isSoccerMode())
+            tipset = "soccer";
+        core::stringw tip = TipsManager::get()->getTip(tipset);
         core::stringw tips_string = _("Tip: %s", tip);
         MessageQueue::add(MessageQueue::MT_GENERIC, tips_string);
     }