Extract basic implementation from ndoh-control

Can we add required settings here? I think they're:
```
SNAPPY_API_KEY = 'keyfromsettings'
SNAPPY_BASE_URL = 'https://app.besnappy.com/api/v1'
SNAPPY_EMAIL = 'sharedmailbox@example.com'
SNAPPY_EXTRAS = ["extra1", "extra2"]
SNAPPY_MAILBOX_ID = 0
SNAPPY_STAFF_ID = 0
VUMI_GO_ACCOUNT_KEY = "key"
VUMI_GO_ACCOUNT_TOKEN = "token"
VUMI_GO_API_TOKEN = "token"
VUMI_GO_API_URL = "http://go.vumi.org/api/v1/go"
VUMI_GO_BASE_URL = VUMI_GO_API_URL + "/http_api_nostream"
VUMI_GO_CONVERSATION_KEY = "convokey"
```