Added missing "uri" data type

SDT/schema2.0/etc/domain.rnc

@@ -54,6 +54,7 @@ DataType =
   | "time"
   | "datetime"
   | "blob"
+  | "uri"
 DocText =
   (text
    | element em { text }

SDT/schema2.0/src/domain.rng

@@ -130,6 +130,7 @@
 			<value>time</value>
 			<value>datetime</value>
 			<value>blob</value>
+			<value>uri</value>
 		</choice>
 	</define>
 

SDT/schema2.0/src/domain.xsd

@@ -98,6 +98,7 @@
       <xs:enumeration value="time"/>
       <xs:enumeration value="datetime"/>
       <xs:enumeration value="blob"/>
+      <xs:enumeration value="uri"/>
     </xs:restriction>
   </xs:simpleType>
   <xs:group name="DocText">