metropolis/resolver: use logging.Leveled

This moves the resover client library to use logging.Leveled instead of
an ad-hoc logger interface.

By now having multiple level of logs, and by defaulting metroctl to show
errors and warnings, this should fix #302.

Change-Id: I7cae1cf1be377ec824ad46ea1da1b23b46e01903
Reviewed-on: https://review.monogon.dev/c/monogon/+/3432
Reviewed-by: Lorenz Brun <lorenz@monogon.tech>
Tested-by: Jenkins CI
diff --git a/metropolis/cli/metroctl/core/BUILD.bazel b/metropolis/cli/metroctl/core/BUILD.bazel
index e65a8a7..3a599a7 100644
--- a/metropolis/cli/metroctl/core/BUILD.bazel
+++ b/metropolis/cli/metroctl/core/BUILD.bazel
@@ -12,6 +12,7 @@
     importpath = "source.monogon.dev/metropolis/cli/metroctl/core",
     visibility = ["//visibility:public"],
     deps = [
+        "//go/logging",
         "//metropolis/node",
         "//metropolis/node/core/curator/proto/api",
         "//metropolis/node/core/rpc",