Small change in Attribute.alias eval to prevent list access in init

ldapalchemy/attribute.py

@@ -40,7 +40,7 @@ class AttributeList(MutableSequence):
 class Attribute:
 	def __init__(self, name, aliases=None, multi=False, default=None):
 		self.name = name
-		self.aliases = aliases or []
+		self.aliases = aliases if aliases is not None else []
 		self.multi = multi
 		self.default = default