Spade edge event protocol

`request_handler/request_handler.go` is the primary work, it basically replaces our line printing with methods from the [spade portion of our protocol](https://github.com/TwitchScience/scoop_protocol/pull/5).

Note this commit also updates Godeps, so there is some noise in the diff.
I believe this should be `json:"receivedAt"`

See: http://golang.org/pkg/encoding/json/#Marshal