samples: add Terra samples

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

samples/Terra/macro2.t

@@ -0,0 +1,14 @@
+
+local bar2 = macro(function(typ)
+	return typ
+	
+end)
+
+terra foo() : int
+	var a = 3
+	bar2(a) = bar2(a) + 5
+	return a
+end
+
+local test = require("test")
+test.eq(8,foo())