WIP rewrite the daemon

cmd subdir does not build on purpose, it's only left in tree to grab old
code and move it to github.com/zrepl/zrepl/daemon

daemon/connecter/connecter.go

@@ -0,0 +1,20 @@
+package connecter
+
+import (
+	"fmt"
+	"github.com/problame/go-streamrpc"
+	"github.com/zrepl/zrepl/config"
+)
+
+func FromConfig(g config.Global, in config.ConnectEnum) (streamrpc.Connecter, error) {
+	switch v := in.Ret.(type) {
+	case *config.SSHStdinserverConnect:
+		return SSHStdinserverConnecterFromConfig(v)
+	case *config.TCPConnect:
+		return TCPConnecterFromConfig(v)
+	case *config.TLSConnect:
+		return TLSConnecterFromConfig(v)
+	default:
+		panic(fmt.Sprintf("implementation error: unknown connecter type %T", v))
+	}
+}