samples: add Terra samples

source: https://github.com/zdevito/terra/tree/master/tests

samples/Terra/recstruct2.t

@@ -0,0 +1,17 @@
+
+
+local struct A { b : &B }
+  and struct B { a : &A }
+
+struct C { a : &A, b : &B, c : &C  }
+
+local struct D {}
+
+terra foo()
+	var a : A, b : B, c : C
+	a.b = &b
+	b.a = &a
+	c.c = &c
+end
+
+foo()