veyron/lib/signals, veyron2/vlog: use new modules package for testing.
veyron/lib/signals, veyron2/vlog: use new modules package for testing.

Change-Id: I28a4653530c5627d242cf82eced085a4b27d14d1

vanadium/go.v23,vanadium/go.v23,vanadium/go.v23