Update help.coffee to replace 'hubot' with robot name

[iojw]

Currently, the help.coffee page generates a webpage displaying commands using the default name 'hubot'. We should be able to update this dynamically with the actual name of the bot.

[iojw]

Take a look at https://github.com/hubotio/hubot-help/blob/master/src/help.js#L110 as it seems to accomplish this