General fixes

+Fixed a bug that didn't permit to display the bonus of some buildings
at level 0
+The cavalry training percentage bonus, provided by the horsedrinking
trough, is now displayed correctly

GameEngine/Battle.php

@@ -464,7 +464,7 @@ class Battle {
         $winner = ($rap > $rdp);
 
         // Formula for calculating the Moral
-        // WW villages aren't affected by this moral bonus
+        // WW villages aren't affected by this bonus
         if($attpop > $defpop && !$isWWVillage) {
             $moralbonus = 1 / round(max(0.667, pow($defpop / $attpop, 0.2 * min(1, $rap / ($rdp > 0 ? $rdp : 1)))), 3);  
         }

GameEngine/Lang/en.php

@@ -1113,6 +1113,7 @@ define("WORLD_WONDER_NOTCHANGE_NAME","You can not change the name of the World W
 define("WORLD_WONDER_NAME_CHANGED","Name changed");
 
 define("HORSEDRINKING","Horse Drinking Trough");
+define("EXTRA_BONUS","Extra bonus");
 define("HORSEDRINKING_DESC","The horse drinking trough of the Romans decreases the training time of cavalry and the upkeep of these troops as well.");
 
 define("GREATWORKSHOP","Great Workshop");