fix bugs with tls and api url, see details bellow

* Add CRANE_DOCKER_ENTRY_SCHEME in deploy/env, to use docker
  over ssl, must set CRANE_DOCKER_TLS_VERIFY=true and
  CRANE_DOCKER_ENTRY_SCHEME=https at the same time.
* add missing close quote in field tag, DockerTlsVerify wat not
  properly unmarshalled.
* use url.Parse() to initialize Url object, fix error:

    time="2017-09-08T14:58:14+08:00" level=warning msg="get node list error: Get ./https://192.168.x.x:2376/nodes: unsupported protocol scheme \"\""

  note "./" before "https://..."

deploy/env

@@ -1,6 +1,7 @@
 CRANE_ADDR=0.0.0.0:5013
 CRANE_SWARM_MANAGER_IP
 CRANE_DOCKER_TLS_VERIFY=false
+CRANE_DOCKER_ENTRY_SCHEME=http
 CRANE_DOCKER_ENTRY_PORT=2375
 CRANE_DOCKER_API_VERSION=1.24
 CRANE_DOCKER_CERT_PATH=null

src/utils/config/config.go

@@ -15,7 +15,7 @@ type Config struct {
 	DbDriver          string   `env:"CRANE_DB_DRIVER,required"`
 	DbDSN             string   `env:"CRANE_DB_DSN,required"`
 	FeatureFlags      []string `env:"CRANE_FEATURE_FLAGS,required"`
-	DockerTlsVerify   bool     `env:"CRANE_DOCKER_TLS_VERIFY envDefault:"false"`
+	DockerTlsVerify   bool     `env:"CRANE_DOCKER_TLS_VERIFY" envDefault:"false"`
 
 	// registry
 	RegistryPrivateKeyPath string `env:"CRANE_REGISTRY_PRIVATE_KEY_PATH,required"`

src/utils/httpclient/client.go

@@ -290,9 +290,7 @@ func (cli *Client) newRequest(method, path string, query url.Values, body io.Rea
 // returns the versioned request path to call the api.
 // It appends the query parameters to the path if they are not empty.
 func getAPIPath(apiPath string, query url.Values) string {
-	u := &url.URL{
-		Path: apiPath,
-	}
+	u, _ := url.Parse(apiPath)
 	if len(query) > 0 {
 		u.RawQuery = query.Encode()
 	}