Handle networks.driver_opts for a service

These are endpoint-specific driver options...

services:
  myservice:
    image: myimage
    networks:
      mynet:
        driver_opts:
          "option1": "value1"

The API has had support for a long time, it's only recently been
added to compose (unreleased right now).

Signed-off-by: Rob Murray <rob.murray@docker.com>

cli/compose/loader/full-example.yml

@@ -207,6 +207,9 @@ services:
         aliases:
          - alias1
          - alias3
+        driver_opts:
+          "driveropt1": "optval1"
+          "driveropt2": "optval2"
       other-network:
         ipv4_address: 172.16.238.10
         ipv6_address: 2001:3984:3989::10

cli/compose/loader/full-struct_test.go

@@ -190,6 +190,10 @@ func services(workingDir, homeDir string) []types.ServiceConfig {
 					Aliases:     []string{"alias1", "alias3"},
 					Ipv4Address: "",
 					Ipv6Address: "",
+					DriverOpts: map[string]string{
+						"driveropt1": "optval1",
+						"driveropt2": "optval2",
+					},
 				},
 				"other-network": {
 					Ipv4Address: "172.16.238.10",

cli/compose/loader/testdata/full-example.json.golden

@@ -285,7 +285,11 @@
           "aliases": [
             "alias1",
             "alias3"
-          ]
+          ],
+          "driver_opts": {
+            "driveropt1": "optval1",
+            "driveropt2": "optval2"
+          }
         }
       },
       "pid": "host",

cli/compose/loader/testdata/full-example.yaml.golden

@@ -152,6 +152,9 @@ services:
         aliases:
         - alias1
         - alias3
+        driver_opts:
+          driveropt1: optval1
+          driveropt2: optval2
     pid: host
     ports:
     - mode: ingress