issue: vouchers call

[SirBillyMays]

message:
"Traceback (most recent call last):
File "/usr/local/lib/python3.5/site-packages/slackbot/dispatcher.py", line 55, in _dispatch_msg_handler
func(Message(self._client, msg), *args)
File "/usr/src/app/plugins/in.py", line 27, in vouchers
wallets = get_from_api(base_url + 'voucher/wallets?user=' + username)
File "/usr/src/app/plugins/util.py", line 27, in get_from_api
response.encoding = chardet.detect(response.raw.data)['encoding']
AttributeError: '_RawStore' object has no attribute 'data'"

Recently changed username, now vouchers crashes.