#692 Allow to set a default value for AttributeDuration (was forced to 0 anytime)

git-svn-id: http://svn.code.sf.net/p/itop/code/trunk@2705 a333f486-631f-4898-b8df-5754b55c2be0

core/attributedef.class.inc.php

@@ -2649,10 +2649,6 @@ class AttributeDuration extends AttributeInteger
 	protected function GetSQLCol() {return "INT(11) UNSIGNED";}
 
 	public function GetNullValue() {return '0';}
-	public function GetDefaultValue()
-	{
-		return 0;
-	}
 
 	public function MakeRealValue($proposedValue, $oHostObj)
 	{