Add hysteria and acme TLS certificate issuer (#18)

* Add hysteria client/server
* Add acme TLS certificate issuer

inbound/tls_acme_stub.go

@@ -0,0 +1,16 @@
+//go:build !with_acme
+
+package inbound
+
+import (
+	"context"
+	"crypto/tls"
+
+	"github.com/sagernet/sing-box/adapter"
+	"github.com/sagernet/sing-box/option"
+	E "github.com/sagernet/sing/common/exceptions"
+)
+
+func startACME(ctx context.Context, options option.InboundACMEOptions) (*tls.Config, adapter.Service, error) {
+	return nil, nil, E.New(`ACME is not included in this build, rebuild with -tags with_acme`)
+}