Add AIM adapter

fixes #645
fix two spelling mistakes in docs/scripting.md
Merge pull request #654 from adamvduke/patch-1

fix two spelling mistakes in docs/scripting.md
fix making a user an admin multiple times over
expose the robot adapter via adapterName
Merge pull request #663 from github/ugh

Expose the robot adapter via adapterName
Merge pull request #661 from lusis/admin_admin_admin_admin

fix making a user an admin multiple times over
use any registered extension
added Slack adapter to the list
Merge pull request #671 from Restuta/patch-1

added Slack adapter to the list
Add Lingr adapter
Add a quick note about Script Load Order. Fixes #675
Merge pull request #677 from miyagawa/adapter-lingr

Add Lingr adapter
Merge pull request #667 from jbr/master

Alllow hubot scripts to be written in other languages
Version bump 2.7.3
Close trailing backtick
Prefer rediscloud over redistogo, because it's free plan includes persistence
Merge pull request #689 from github/heroku-redis-addon

Prefer rediscloud over redistogo for heroku
Specify a User-Agent for Campfire, to avoid as strict rate limiting
Include user agent here too