be sure to retrain after enable voice-controller

[kgiori]

I had updated to a version 1.0 voice-controller add-on on a 0.8.1 gateway that had the previous voice-controller version. When I plugged the speaker/mic back into it (had been detached), I disabled/enabled the voice-controller. Note to self -- because packages are uninstalled and re-installed for this process, you have to go have coffee or something while waiting (takes a long time on a little RPi.) After updating the config to "hey snips" and waiting some more, then the wake word was being detected, but it failed on a simple command, "turn on the balcony" (a light). I suspect the problem is that after reconfig/retrain/reinstall/restart, somehow the controller didn't "start up" with a known set of thing names in its language model (LM). After I had deleted a thing from my UI, I saw that the voice-controller had done a "retrain" event (saw in log). When I tried a voice command again, it recognized all my thing names. :) So I think that after every "configure" or "enable" of the voice-controller, we should make sure to also run the "retrain" process to make sure the LM is up to date.