Log extra environment information (#95)

* Make metrics tests use a host port

* fix port forwarding in devconfig tests

* Log extra environment information at startup

vendor/github.com/genuinetools/amicontained/container/container_test.go

@@ -0,0 +1,41 @@
+package container
+
+import (
+	"testing"
+)
+
+func TestReadUserMappings(t *testing.T) {
+	f := `         0     100000       1000
+      1000       1000          1
+      1001     101001      64535`
+	expected := []UserMapping{
+		{
+			ContainerID: 0,
+			HostID:      100000,
+			Range:       1000,
+		},
+		{
+			ContainerID: 1000,
+			HostID:      1000,
+			Range:       1,
+		},
+		{
+			ContainerID: 1001,
+			HostID:      101001,
+			Range:       64535,
+		},
+	}
+
+	userNs, mappings, err := readUserMappings(f)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if !userNs {
+		t.Fatal("expected user namespaces to be true")
+	}
+
+	if len(expected) != len(mappings) {
+		t.Fatalf("expected length %d got %d", len(expected), len(mappings))
+	}
+}