Add an echo client to be used instead of nc.

nc behaviour depends on the implementation version of what's on the current host.
Here we use our own client with stable behaviour.

Signed-off-by: Federico Paolinelli <fpaoline@redhat.com>

pkg/testutils/echo/init_test.go

@@ -0,0 +1,13 @@
+package main_test
+
+import (
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+
+	"testing"
+)
+
+func TestEchosvr(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "pkg/testutils/echosvr")
+}