add xml configuration validation

Author: [email protected]

src/NHibernate.Test/App.config

@@ -38,6 +38,7 @@
 			<property name="cache.use_query_cache">true</property>
 
 			<property name="query.startup_check">false</property>
+			<property name="query.throw_never_cached">true</property>
 			<property name="query.substitutions">true 1, false 0, yes 'Y', no 'N'</property>
 
 			<property name="adonet.batch_size">10</property>

src/NHibernate/nhibernate-configuration.xsd

@@ -149,6 +149,7 @@
 										<xs:enumeration value="xml.output_stylesheet" />
 										<xs:enumeration value="generate_statistics" />
 										<xs:enumeration value="query.startup_check" />
+										<xs:enumeration value="query.throw_never_cached" />
 										<xs:enumeration value="default_catalog" />
 										<xs:enumeration value="proxyfactory.factory_class" />
 										<xs:enumeration value="adonet.factory_class" />