The V2 Calls api endpoints have been added beneath fns: (#1203)

/fns/{fnID}/calls
/fns/{fnID}/calls/{callID}

The S3 implementation forces our hand as we if we want to list Calls
under a Fn, we have to use the FnID as a prefix on the object names,
which mean we need it to look up any Call. It also makes sense in
terms of resource hierarchy.

These endpoints can optionally be disabled (as other endpoints), if a
service provider needs to provide this functionality via other means.

The 'calls' test has been fully migrated to fn calls. This has been
done to reduce the copy pasta a bit, and on balance is ok as the
routes calls will be removed soon.

api/models/call.go

@@ -163,8 +163,14 @@ type Call struct {
 type CallFilter struct {
 	Path     string // match
 	AppID    string // match
+	FnID     string //match
 	FromTime common.DateTime
 	ToTime   common.DateTime
 	Cursor   string
 	PerPage  int
 }
+
+type CallList struct {
+	NextCursor string  `json:"next_cursor,omitempty"`
+	Items      []*Call `json:"items"`
+}