go: re-do the entire thing

This is a mega-change, but attempting to split this up further is
probably not worth the effort.

Summary:

1. Bump up bazel, rules_go, and others.
2. Switch to new go target naming (bye bye go_default_library)
3. Move go deps to go.mod/go.sum, use make gazelle generate from that
4. Bump up Python deps a bit

And also whatever was required to actually get things to work - loads of
small useless changes.

Tested to work on NixOS and Ubuntu 20.04:

   $ bazel build //...
   $ bazel test //...

Change-Id: I8364bdaa1406b9ae4d0385a6b607f3e7989f98a9
Reviewed-on: https://gerrit.hackerspace.pl/c/hscloud/+/1583
Reviewed-by: q3k <q3k@hackerspace.pl>
diff --git a/devtools/ci/remote-cache/BUILD.bazel b/devtools/ci/remote-cache/BUILD.bazel
index 4d46955..056a371 100644
--- a/devtools/ci/remote-cache/BUILD.bazel
+++ b/devtools/ci/remote-cache/BUILD.bazel
@@ -1,7 +1,7 @@
 load("@io_bazel_rules_go//go:def.bzl", "go_binary", "go_library")
 
 go_library(
-    name = "go_default_library",
+    name = "remote-cache_lib",
     srcs = [
         "main.go",
         "service.go",
@@ -9,15 +9,15 @@
     importpath = "code.hackerspace.pl/hscloud/devtools/ci/remote-cache",
     visibility = ["//visibility:private"],
     deps = [
-        "//go/mirko:go_default_library",
-        "@com_github_golang_glog//:go_default_library",
-        "@com_github_minio_minio_go_v7//:go_default_library",
-        "@com_github_minio_minio_go_v7//pkg/credentials:go_default_library",
+        "//go/mirko",
+        "@com_github_golang_glog//:glog",
+        "@com_github_minio_minio_go_v7//:minio-go",
+        "@com_github_minio_minio_go_v7//pkg/credentials",
     ],
 )
 
 go_binary(
     name = "remote-cache",
-    embed = [":go_default_library"],
+    embed = [":remote-cache_lib"],
     visibility = ["//visibility:public"],
 )