Add character data markup to fix XML validation

Fix suggested by @andylolz in #252 (comment)

xml/OrganisationRegistrationAgency.xml

@@ -4,15 +4,15 @@
             <narrative>Organisation Registration Agency</narrative>
         </name>
         <description>
-            <narrative>
-                The values from this codelist are used to identify the particular list that an organisation identifier was drawn from. The codelist provides a register of known identifier lists, including national company registers, NGO directories and international and multilateral organisation lists - along with guidance and online resources to help locate the identifiers assigned to a specific organisation. 
-                
-                As of 17 July 2017 this list is maintained by the org-id.guide project. Data publishers can now search for and locate the relevant list for a particular organisation identifier using the `org-id.guide website <http://org-id.guide/>`__. The full register of identifier sources is also available to download in `XML <http://org-id.guide/download.xml>`__, `JSON <http://org-id.guide/download.json>`__ and `CSV <http://org-id.guide/download.csv>`__ formats. 
-                
+            <narrative><![CDATA[
+                The values from this codelist are used to identify the particular list that an organisation identifier was drawn from. The codelist provides a register of known identifier lists, including national company registers, NGO directories and international and multilateral organisation lists - along with guidance and online resources to help locate the identifiers assigned to a specific organisation.
+
+                As of 17 July 2017 this list is maintained by the org-id.guide project. Data publishers can now search for and locate the relevant list for a particular organisation identifier using the `org-id.guide website <http://org-id.guide/>`__. The full register of identifier sources is also available to download in `XML <http://org-id.guide/download.xml>`__, `JSON <http://org-id.guide/download.json>`__ and `CSV <http://org-id.guide/download.csv>`__ formats.
+
                 IATI periodically replicates the codelist of identifier sources from org-id.guide, to assist those accessing IATI documentation. However, it is advised that the most up-to-date source is the c.
-                
+
                 If org-id.guide does not contain an entry for the kind of organisation you need to identify, you can make a request a new list is included in the register following the `guidance <http://docs.org-id.guide/en/latest/contribute/>`__ or by getting in touch with org-id.guide at: [email protected].
-            </narrative>
+            ]]></narrative>
         </description>
     </metadata>
     <codelist-items>