samples: add Terra samples

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

samples/Terra/overloadcall.t

@@ -0,0 +1,12 @@
+
+
+terra foo(a : int)
+	return a
+end
+
+terra foo(a : int, b : int)
+	return a + b
+end
+
+local test = require("test")
+test.eq(foo(1) + foo(3,4), 8)