added configuration option for Sql Server 2012

Author: chester89

src/FluentNHibernate.Testing/Cfg/Db/MsSqlConfigurationTester.cs

@@ -39,6 +39,14 @@ public void MsSql2008_should_default_to_the_Sql2008_dialect()
                 .ShouldContain("dialect", "NHibernate.Dialect.MsSql2008Dialect, " + typeof(ISession).Assembly.FullName);
         }
 
+        [Test]
+        public void MsSql2012_should_default_to_thee_Sql2012_dialect()
+        {
+            MsSqlConfiguration.MsSql2012
+                .ToProperties()
+                .ShouldContain("dialect", "NHibernate.Dialect.MsSql2012Dialect, " + typeof(ISession).Assembly.FullName);
+        }
+
         [Test]
         public void MsSql_driver_should_default_to_the_SqlClientDriver()
         {

src/FluentNHibernate/Cfg/Db/MsSqlConfiguration.cs

@@ -29,5 +29,10 @@ public static MsSqlConfiguration MsSql2008
         {
             get { return new MsSqlConfiguration().Dialect<MsSql2008Dialect>(); }
         }
+
+        public static MsSqlConfiguration MsSql2012
+        {
+            get { return new MsSqlConfiguration().Dialect<MsSql2012Dialect>(); }
+        }
     }
 }