isolate and mark platform dependent code

now unit tests compile on OS X and (some of them) work

util/util_test.go

@@ -0,0 +1,22 @@
+package util
+
+import (
+	"github.com/stretchr/testify/require"
+	"strings"
+	"testing"
+)
+
+func TestLoadResourceSimple(t *testing.T) {
+	assert := require.New(t)
+
+	expected := `services:
+- debian-console
+- ubuntu-console
+`
+	expected = strings.TrimSpace(expected)
+
+	b, e := LoadResource("https://raw.githubusercontent.com/rancherio/os-services/v0.3.4/index.yml", true, []string{})
+
+	assert.Nil(e)
+	assert.Equal(expected, strings.TrimSpace(string(b)))
+}