Updated yeoman initialization step
Updated yeoman initialization step

Removed the `npm install hubot-slack step`.  If you change the adapter from the default configuration ('campfire') during `yo hubot` interactive setup (or with the --adapter=slack flag), the hubot-slack module will be installed for you as the final dependency.  Using npm to install it again is redundant.
bufferapp/bufferbot-slack,stackriot/octobot