Outbound Recording

Where Plivo hands back the recording of a callback.

The twin of /inbound/recording, and deliberately a SEPARATE route: that one creates a voice_call row for a voicemail nobody had a row for yet. A callback already has its row, with its ticket on it, written before the first leg was even placed -- so this only ever fills the recording in. Creating a second row here would put a call on the board twice and detach the recording from the ticket it belongs to.