Set Spring.build to allow compilation on x64 machines with NAnt 0.86 (sysinfo failonerror=false) and fixed NHibernate test build file

test/Spring/Spring.Data.NHibernate.Tests/Data/NHibernate/LocalSessionFactoryObjectTests.cs

@@ -23,7 +23,9 @@
 using System.Collections;
 using System.IO;
 using NHibernate;
+#if NH_2_1
 using NHibernate.ByteCode.LinFu;
+#endif
 using NHibernate.Cfg;
 using NHibernate.Connection;
 using NHibernate.Dialect;