samples: add Terra samples

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

samples/Terra/bug3.t

@@ -0,0 +1,15 @@
+
+
+local S = terralib.types.newstruct("mystruct")
+
+struct A {
+	v : int
+}
+
+S.entries:insert( { type = A, field = "what" } )
+terra foo()
+	var v : S
+	return v.what.v
+end
+
+foo:compile()