add schema

sshpiperd/e2e/sshpiperd.yaml

@@ -1,4 +1,5 @@
-version: 1
+# yaml-language-server: $schema=https://raw.githubusercontent.com/tg123/sshpiper/master/sshpiperd/upstream/yaml/schema.json
+version: "0.1"
 pipes:
   - username: passthrough
     upstream_host: host2

sshpiperd/upstream/yaml/pipemgr.go

@@ -145,7 +145,7 @@ func (p *plugin) CreatePipe(opt upstream.CreatePipeOption) error {
 		fmt.Fprintln(&buf)
 
 		out, err := yaml.Marshal(piperConfig{
-			Version: 1,
+			Version: "0.1",
 			Pipes:   []pipeConfig{toPipeConfig(opt)},
 		})
 

sshpiperd/upstream/yaml/yaml.go

@@ -52,7 +52,7 @@ type pipeConfig struct {
 }
 
 type piperConfig struct {
-	Version int          `yaml:"version"`
+	Version string       `yaml:"version"`
 	Pipes   []pipeConfig `yaml:"pipes,flow"`
 }