Move updateAvailableGenerators() elsewhere, try to make it stateless

[sindresorhus]

https://github.com/yeoman/yo/blob/d40dbdfff32e335700bbed63f9953d32b5ae1072/lib/router.js#L52

// @SBoudrias

[wtgtybhertgeghgtwtg]

I might be missing something, but what is the point of this.generators? It's created and assigned to but never used.

[teobais]

Good point @wtgtybhertgeghgtwtg . Could anybody enlighten us here?

[SBoudrias]

Ah, routes are receiving the router instance as argument. It must be used in a route: https://github.com/yeoman/yo/blob/d40dbdfff32e335700bbed63f9953d32b5ae1072/lib/router.js#L35