m/c/metroctl: add MVP disk/image-only installer

This adds a very minimalist metroctl install command.
Only supports boostrapping and a single owner key.
But good enough to set up a node.

Change-Id: I9306a054b9540a3a0c70621f3f5d9cb34fc18d14
Reviewed-on: https://review.monogon.dev/c/monogon/+/417
Reviewed-by: Mateusz Zalega <mateusz@monogon.tech>
diff --git a/third_party/go/repositories.bzl b/third_party/go/repositories.bzl
index 2bee624..ef9f9c8 100644
--- a/third_party/go/repositories.bzl
+++ b/third_party/go/repositories.bzl
@@ -93,6 +93,16 @@
         ],
     )
     go_repository(
+        name = "com_github_adrg_xdg",
+        importpath = "github.com/adrg/xdg",
+        version = "v0.4.0",
+        sum = "h1:RzRqFcjH4nE5C6oTAxhBtoE2IRyjBSa62SCbyPidvls=",
+        build_extra_args = [
+            "-go_naming_convention=go_default_library",
+            "-go_naming_convention_external=go_default_library",
+        ],
+    )
+    go_repository(
         name = "com_github_alexflint_go_filemutex",
         importpath = "github.com/alexflint/go-filemutex",
         version = "v0.0.0-20171022225611-72bdc8eae2ae",
diff --git a/third_party/go/shelf.pb.text b/third_party/go/shelf.pb.text
index de2f33e..a2f816b 100644
--- a/third_party/go/shelf.pb.text
+++ b/third_party/go/shelf.pb.text
@@ -111,6 +111,13 @@
   semver: "v0.0.0-20170810143723-de5bf2ad4578"
 >
 entry: <
+  import_path: "github.com/adrg/xdg"
+  version: "v0.4.0"
+  bazel_name: "com_github_adrg_xdg"
+  sum: "h1:RzRqFcjH4nE5C6oTAxhBtoE2IRyjBSa62SCbyPidvls="
+  semver: "v0.4.0"
+>
+entry: <
   import_path: "github.com/alexflint/go-filemutex"
   version: "v0.0.0-20171022225611-72bdc8eae2ae"
   bazel_name: "com_github_alexflint_go_filemutex"