Remove grafana.coffee

Proposing the deprecation of this in favor of the [hubot-grafana](https://www.npmjs.com/package/hubot-grafana) package, which offers cross-adapter support, dashboard browsing and can be augmented with Amazon S3 credentials.

Fixes #2206

vendor/grafana.coffee

-# Description:
-#   A way to interact with the Google Images API.
-#
-# Commands:
-#   hubot image me <query> - The Original. Queries Google Images for <query> and returns a random top result.
-#   hubot animate me <query> - The same thing as `image me`, except adds a few parameters to try to return an animated GIF instead.
-#   hubot mustache me <url> - Adds a mustache to the specified URL.
-#   hubot mustache me <query> - Searches Google Images for the specified query and mustaches it.
-
-module.exports = (robot) ->
-  robot.hear /grafana (.*)/i, (msg) ->
-    sendUrl msg.match[1]
-
-  robot.router.get '/hubot/test', (req, res) ->
-    sendUrl()
-    res.send 'OK '
-
-imageMe = (msg, cb) ->
-  cb 'http://localhost:3000/render/dashboard/solo/grafana-play-home?from=now-1h&to=now&panelId=4&fullscreen'
-
-sendUrl = (params) ->
-  https = require 'https'
-  querystring = require 'querystring'
-  opts = params.split(' ')
-  dashboard = opts[0]
-  panelId = opts[1]
-  from = opts[2]
-
-  imageUrl = "http://localhost:3000/render/dashboard/solo/#{dashboard}/?panelId=#{panelId}"
-  link = "http://localhost:3000/dashboard/db/#{dashboard}/?panelId=#{panelId}&fullscreen"
-  if from
-    imageUrl += "&from=#{from}"
-    link += "&from=#{from}"
-
-  console.log 'imageUrl: ' + imageUrl
-
-  hipchat = {}
-  hipchat.format = 'json'
-  hipchat.auth_token = process.env.HUBOT_HIPCHAT_TOKEN
-  console.log 'token: ' + hipchat.auth_token
-
-  hipchat.room_id = '877465'
-  hipchat.message = "<a href='#{link}'><img src='#{imageUrl}'></img></a>"
-  hipchat.from = "hubot"
-  hipchat.message_format = "html"
-
-  params = querystring.stringify(hipchat)
-
-  path = "/v1/rooms/message/?#{params}"
-
-  data = ''
-
-  https.get {host: 'api.hipchat.com', path: path}, (res) ->
-      res.on 'data', (chunk) ->
-          data += chunk.toString()
-      res.on 'end', () ->
-          json = JSON.parse(data)
-          console.log "Hipchat response ", data
-
-