samples: add Terra samples

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

samples/Terra/abouttocompile.t

@@ -0,0 +1,22 @@
+struct A {
+	a : int;
+	b : int;
+}
+
+function A.metamethods.__getentries(self)
+	print("GET ENTRIES")
+	for i,e in ipairs(self.entries) do
+		e.field = "foo"..e.field
+	end
+	return self.entries
+end
+
+terra foo()
+	var a : A
+	a.fooa = 3
+	a.foob = 4
+	return a.fooa + a.foob
+end
+
+
+assert(foo() == 7)