Updated 2.1 spec

Author: akarimova

specification/2.1/appdf-description.xsd

@@ -499,7 +499,7 @@
 
     <xsd:complexType name="type-subscriptions">
         <xsd:sequence>
-            <xsd:element name="subscription" type="type-in-app-subscription" maxOccurs="unbounded"/>
+            <xsd:element name="subscription" type="type-in-app-subscription" minOccurs="0" maxOccurs="unbounded"/>
         </xsd:sequence>
     </xsd:complexType>
 
@@ -511,7 +511,7 @@
 
     <xsd:complexType name="type-items">
         <xsd:sequence>
-            <xsd:element name="item" type="type-in-app-item" maxOccurs="unbounded"/>
+            <xsd:element name="item" type="type-in-app-item" minOccurs="0" maxOccurs="unbounded"/>
         </xsd:sequence>
     </xsd:complexType>