`test_bot_channel_reply_to_name_colon` fails on develop branch

Steps to reproduce:

I checkout the repository
Created a new slack
Created a bot user
Created an API token for me

Set up the test file like this:

testbot_apitoken = '... redacted ...'
testbot_username = 'slackbot-test'
driver_apitoken = '... redacted ...'
driver_username = 'csaftoiu'
test_channel = 'testchannel'
test_group = 'testprivate'

Run py.test like so:
```
$ py.test -k test_bot_channel_reply
```

And the error is:

platform darwin -- Python 3.5.1, pytest-2.9.2, py-1.4.31, pluggy-0.3.1 -- /Users/csaftoiu/csaftoiu-github/slackbot/.env/bin/python3.5
cachedir: .cache
rootdir: /Users/csaftoiu/csaftoiu-github/slackbot, inifile: pytest.ini
collected 39 items

tests/functional/test_functional.py::test_bot_channel_reply_to_name_colon [06/23/2016 19:57:57] using aliases !,$
[06/23/2016 19:57:57] loading plugin "slackbot.plugins"
[06/23/2016 19:57:57] registered respond_to plugin "hello_reply" to "hello$"
[06/23/2016 19:57:57] registered respond_to plugin "hello_webapi" to "^reply_webapi$"
[06/23/2016 19:57:57] registered respond_to plugin "hello_webapi_not_as_user" to "^reply_webapi_not_as_user$"
[06/23/2016 19:57:57] registered respond_to plugin "hello_reply_formatting" to "hello_formatting"
[06/23/2016 19:57:57] registered listen_to plugin "hello_send" to "hello$"
[06/23/2016 19:57:57] registered respond_to plugin "hello_decorators" to "hello_decorators"
[06/23/2016 19:57:57] registered listen_to plugin "hello_decorators" to "hello_decorators"
[06/23/2016 19:57:57] registered listen_to plugin "hey" to "hey!"
[06/23/2016 19:57:57] registered respond_to plugin "hello_unicode_message" to "你好"
[06/23/2016 19:57:57] registered respond_to plugin "upload" to "upload \<?(.*)\>?"
[06/23/2016 19:57:59] connected to slack RTM api
[06/23/2016 19:57:59] keep active thread started
FAILED

===================================================== FAILURES ======================================================
_______________________________________ test_bot_channel_reply_to_name_colon ________________________________________

driver = <tests.functional.driver.Driver object at 0x10d193e48>

def test_bot_channel_reply_to_name_colon(driver):
  driver.send_channel_message('hello', tobot=False, toname=True)
>       driver.wait_for_bot_channel_message('hello sender!')

tests/functional/test_functional.py:120:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
tests/functional/driver.py:91: in wait_for_bot_channel_message
self._wait_for_bot_message(self.cm_chan, match, tosender=tosender)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = <tests.functional.driver.Driver object at 0x10d193e48>, channel = 'C1KSS1QKE', match = 'hello sender!'
maxwait = 60, tosender = True

def _wait_for_bot_message(self, channel, match, maxwait=60, tosender=True):
  for _ in range(maxwait):
      time.sleep(1)
      if self._has_got_message_rtm(channel, match, tosender):
          break
  else:
>           raise AssertionError('expected to get message like "{}", but got nothing'.format(match))
E           AssertionError: expected to get message like "hello sender!", but got nothing

tests/functional/driver.py:146: AssertionError
================================= 38 tests deselected by '-ktest_bot_channel_reply' =================================
===================================== 1 failed, 38 deselected in 65.01 seconds ======================================

On the Slack channel, the exchange is:

csaftoiu>
slackbot-test: hello

slackbot-test>
hello channel!

That is, it thinks it's to the channel, not to the bot itself.

scrapinghub / slackbot

`test_bot_channel_reply_to_name_colon` fails on develop branch #94