fix: add default HandleIdentifierProvider for disabled versioning

Setting versioning.enabled = false in versioning.cfg is not enough to
disable versioning. It is also required to replace the bean class
VersionedHandleIdentifierProvider with a HandleIdentifierProvider
in identifier-service.xml. I've added one that is commented out as by
default versioning is enabled.

dspace/config/spring/api/identifier-service.xml

@@ -4,14 +4,21 @@
        xsi:schemaLocation="http://www.springframework.org/schema/beans
            http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">
 
-    <!-- Identifier Service Application Interface.  Will be autowired with
+    <!-- Identifier Service Application Interface. Will be autowired with
          any Identifier Providers present in Spring context.
     -->
     <bean id="org.dspace.identifier.service.IdentifierService"
           class="org.dspace.identifier.IdentifierServiceImpl"
           autowire="byType"
           scope="singleton"/>
 
+    <!-- If you disable versioning, you need to use the default HandleIdentifierProvider. -->
+    <!--
+    <bean id="org.dspace.identifier.HandleIdentifierProvider" class="org.dspace.identifier.HandleIdentifierProvider" scope="singleton">
+        <property name="configurationService" ref="org.dspace.services.ConfigurationService"/>
+    </bean>
+    -->
+
       <!-- If you enabled versioning, you should use one of the versioned
            handle identifier provider instead of the default one.
            The VersionedHandleIdentifierProvider creates a new versioned
@@ -26,7 +33,7 @@
            a new version is created the previous version gets a new
            handle. This leads to a handle that points always to the
            newest version, but there is no permanent handle, that
-           will always keep pointing to the acutal newest one.
+           will always keep pointing to the actual newest one.
            -->
     <!--
     <bean id="org.dspace.identifier.HandleIdentifierProvider" class="org.dspace.identifier.VersionedHandleIdentifierProviderWithCanonicalHandles" scope="singleton">