treewide: introduce osbase package and move things around

All except localregistry moved from metropolis/pkg to osbase,
localregistry moved to metropolis/test as its only used there anyway.

Change-Id: If1a4bf377364bef0ac23169e1b90379c71b06d72
Reviewed-on: https://review.monogon.dev/c/monogon/+/3079
Tested-by: Jenkins CI
Reviewed-by: Serge Bazanski <serge@monogon.tech>
diff --git a/metropolis/node/build/mkverity/mkverity.go b/metropolis/node/build/mkverity/mkverity.go
index f44b601..ff2807b 100644
--- a/metropolis/node/build/mkverity/mkverity.go
+++ b/metropolis/node/build/mkverity/mkverity.go
@@ -19,7 +19,7 @@
 // outputs a Verity mapping table on success.
 //
 // For more information, see:
-// - source.monogon.dev/metropolis/pkg/verity
+// - source.monogon.dev/osbase/verity
 // - https://gitlab.com/cryptsetup/cryptsetup/wikis/DMVerity
 package main
 
@@ -30,7 +30,7 @@
 	"log"
 	"os"
 
-	"source.monogon.dev/metropolis/pkg/verity"
+	"source.monogon.dev/osbase/verity"
 )
 
 // createImage creates a dm-verity target image by combining the input image