added Gnmi and Restconf description

nucleus/gnmi_transport.go

@@ -11,6 +11,8 @@ import (
 	"strings"
 )
 
+// Gnmi implements the Transport interface and provides an SBI with the
+// possibility to access a gNMI endpoint.
 type Gnmi struct {
 	SetNode   func(schema *yang.Entry, root interface{}, path *gpb.Path, val interface{}, opts ...ytypes.SetNodeOpt) error
 	RespChan  chan *gpb.SubscribeResponse

nucleus/restconf_transport.go

@@ -5,6 +5,8 @@ import (
 	"github.com/openconfig/ygot/ytypes"
 )
 
+// Restconf implements the Transport interface and provides an SBI with the
+// possibility to access a Restconf endpoint.
 type Restconf struct {
 }