samples: add Terra samples

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

samples/Terra/incomplete.t

@@ -0,0 +1,32 @@
+
+
+struct A
+
+terra foo(a : &A)
+	return a
+end
+
+assert(nil == foo(nil))
+assert(false == A:iscomplete())
+
+
+struct A {
+	b : int
+}
+
+terra foo2(a : &A)
+	a.b = 6
+	return @a
+end
+
+foo2:compile()
+assert(true == A:iscomplete())
+
+local ptr = terralib.new(A)
+
+ptr.b = 4
+
+local r = foo2(ptr)
+
+assert(r.b == 6)
+assert(ptr.b == 6)