Provides operations for creating and managing CallFire subscriptions which listen for account events.
CallFire account events, such as
CallFinished, can be listened for (subscribed to) by
registering a postback URI endpoint, either an email address or web service URL, that CallFire can publish
the event info to. Subscription service is used for registering and managing these postback URI endpoints.
A typical use case would be for determining the status of a
SendText request which is an asynchronous operation.
The status of the Text can be obtained either by polling the GetText / QueryText operations (pull strategy) or
more efficiently by registering with Subscription Service a postback internet endpoint URL for receiving
'textsent' and 'textfinished' events to.
Currently supports TextSent, TextFinished, CallFinished, and CampaignFinished events.