treewide: add license header and enable haslicense linter
Change-Id: I873a8d4082d75e8f813d8a726a41187eea7a065e
Reviewed-on: https://review.monogon.dev/c/monogon/+/3825
Tested-by: Jenkins CI
Reviewed-by: Leopold Schabel <leo@monogon.tech>
diff --git a/metropolis/cli/takeover/boot.go b/metropolis/cli/takeover/boot.go
index eb71694..21ca708 100644
--- a/metropolis/cli/takeover/boot.go
+++ b/metropolis/cli/takeover/boot.go
@@ -1,3 +1,6 @@
+// Copyright The Monogon Project Authors.
+// SPDX-License-Identifier: Apache-2.0
+
package main
import (
diff --git a/metropolis/cli/takeover/e2e/main_test.go b/metropolis/cli/takeover/e2e/main_test.go
index 32d7fb8..c9108cd 100644
--- a/metropolis/cli/takeover/e2e/main_test.go
+++ b/metropolis/cli/takeover/e2e/main_test.go
@@ -1,3 +1,6 @@
+// Copyright The Monogon Project Authors.
+// SPDX-License-Identifier: Apache-2.0
+
package e2e
import (
diff --git a/metropolis/cli/takeover/install.go b/metropolis/cli/takeover/install.go
index b0c56d0..005b590 100644
--- a/metropolis/cli/takeover/install.go
+++ b/metropolis/cli/takeover/install.go
@@ -1,3 +1,6 @@
+// Copyright The Monogon Project Authors.
+// SPDX-License-Identifier: Apache-2.0
+
package main
import (
diff --git a/metropolis/cli/takeover/main.go b/metropolis/cli/takeover/main.go
index a609a63..97ed7a4 100644
--- a/metropolis/cli/takeover/main.go
+++ b/metropolis/cli/takeover/main.go
@@ -1,3 +1,6 @@
+// Copyright The Monogon Project Authors.
+// SPDX-License-Identifier: Apache-2.0
+
package main
import (
diff --git a/metropolis/cli/takeover/takeover.go b/metropolis/cli/takeover/takeover.go
index 327d3c1..95420dc 100644
--- a/metropolis/cli/takeover/takeover.go
+++ b/metropolis/cli/takeover/takeover.go
@@ -1,3 +1,6 @@
+// Copyright The Monogon Project Authors.
+// SPDX-License-Identifier: Apache-2.0
+
package main
import (