cleanup 9daa7520ef following bb's comments

This was SVN commit r20763.

binaries/data/mods/public/simulation/components/Trigger.js

@@ -31,7 +31,8 @@ Trigger.prototype.eventNames =
 Trigger.prototype.Init = function()
 {
 	// Difficulty used by trigger scripts (as defined in data/settings/trigger_difficulties.json).
-	this.difficulty = 3;
+	this.difficulty = undefined;
+
 	this.triggerPoints = {};
 
 	// Each event has its own set of actions determined by the map maker.
@@ -335,7 +336,7 @@ Trigger.prototype.DoAction = function(msg)
 /**
  * Level of difficulty used by trigger scripts.
  */
-Trigger.prototype.GetDifficulty = function(diff)
+Trigger.prototype.GetDifficulty = function()
 {
 	return this.difficulty;
 };

binaries/data/mods/public/simulation/data/settings/trigger_difficulties.json

@@ -5,7 +5,7 @@
 		{
 			"Difficulty": 1,
 			"Name": "Very Easy",
-			"Tooltip": "Choose this difficulty if you are discovering 0 A.D.."
+			"Tooltip": "Choose this difficulty if you are discovering 0 A.D."
 		},
 		{
 			"Difficulty": 2,
@@ -15,7 +15,7 @@
 		{
 			"Difficulty": 3,
 			"Name": "Medium",
-			"Tooltip": "Choose this difficulty if you have already a good experience with 0 A.D.."
+			"Tooltip": "Choose this difficulty if you have already a good experience with 0 A.D."
 		},
 		{
 			"Difficulty": 4,

binaries/data/mods/public/simulation/helpers/Setup.js

@@ -43,7 +43,7 @@ function LoadMapSettings(settings)
 			cmpObstructionManager.SetPassabilityCircular(true);
 	}
 
-	if (settings.TriggerDifficulty)
+	if (settings.TriggerDifficulty != undefined)
 		Engine.QueryInterface(SYSTEM_ENTITY, IID_Trigger).SetDifficulty(settings.TriggerDifficulty);
 	else if (settings.SupportedTriggerDifficulties)	// used by Atlas and autostart games
 	{