Update error msg to include value

on line 265 error message did not include the value making it difficult to debug.

Author: jjspetz

dist/Jsonix-min.js

@@ -262,7 +262,7 @@ Jsonix.Util.Ensure={ensureBoolean:function(b){if(!Jsonix.Util.Type.isBoolean(b))
 }},ensureString:function(b){if(!Jsonix.Util.Type.isString(b)){throw new Error("Argument ["+b+"] must be a string.")
 }},ensureNumber:function(b){if(!Jsonix.Util.Type.isNumber(b)){throw new Error("Argument ["+b+"] must be a number.")
 }},ensureNumberOrNaN:function(b){if(!Jsonix.Util.Type.isNumberOrNaN(b)){throw new Error("Argument ["+b+"] must be a number or NaN.")
-}},ensureInteger:function(b){if(!Jsonix.Util.Type.isNumber(b)){throw new Error("Argument must be an integer, but it is not a number.")
+}},ensureInteger:function(b){if(!Jsonix.Util.Type.isNumber(b)){throw new Error("Argument ["+b+"] must be an integer, but it is not a number.")
 }else{if(!Jsonix.Util.NumberUtils.isInteger(b)){throw new Error("Argument ["+b+"] must be an integer.")
 }}},ensureDate:function(b){if(!(b instanceof Date)){throw new Error("Argument ["+b+"] must be a date.")
 }},ensureObject:function(b){if(!Jsonix.Util.Type.isObject(b)){throw new Error("Argument ["+b+"] must be an object.")