Update bazel rules versions

In preparation for updating to go 1.14, we need to at least update rules_go. I updated the other rules while I was at it.

WORKSPACE

@@ -6,19 +6,19 @@ load("@bazel_tools//tools/build_defs/repo:git.bzl", "git_repository")
 
 http_archive(
     name = "io_bazel_rules_go",
-    sha256 = "dbde93957f2a96e6c97edb74e29107b7de1b2b57608b8304401e10326e02c66d",
+    sha256 = "a8d6b1b354d371a646d2f7927319974e0f9e52f73a2452d2b3877118169eb6bb",
     urls = [
-        "https://mirror.bazel.build/github.com/bazelbuild/rules_go/releases/download/v0.22.5/rules_go-v0.22.5.tar.gz",
-        "https://github.com/bazelbuild/rules_go/releases/download/v0.22.5/rules_go-v0.22.5.tar.gz",
+        "https://mirror.bazel.build/github.com/bazelbuild/rules_go/releases/download/v0.23.3/rules_go-v0.23.3.tar.gz",
+        "https://github.com/bazelbuild/rules_go/releases/download/v0.23.3/rules_go-v0.23.3.tar.gz",
     ],
 )
 
 http_archive(
     name = "bazel_gazelle",
-    sha256 = "bfd86b3cbe855d6c16c6fce60d76bd51f5c8dbc9cfcaef7a2bb5c1aafd0710e8",
+    sha256 = "cdb02a887a7187ea4d5a27452311a75ed8637379a1287d8eeb952138ea485f7d",
     urls = [
-        "https://mirror.bazel.build/github.com/bazelbuild/bazel-gazelle/releases/download/v0.21.0/bazel-gazelle-v0.21.0.tar.gz",
-        "https://github.com/bazelbuild/bazel-gazelle/releases/download/v0.21.0/bazel-gazelle-v0.21.0.tar.gz",
+        "https://mirror.bazel.build/github.com/bazelbuild/bazel-gazelle/releases/download/v0.21.1/bazel-gazelle-v0.21.1.tar.gz",
+        "https://github.com/bazelbuild/bazel-gazelle/releases/download/v0.21.1/bazel-gazelle-v0.21.1.tar.gz",
     ],
 )
 
@@ -39,9 +39,9 @@ gazelle_dependencies()
 
 http_archive(
     name = "io_bazel_rules_docker",
-    sha256 = "3efbd23e195727a67f87b2a04fb4388cc7a11a0c0c2cf33eec225fb8ffbb27ea",
-    strip_prefix = "rules_docker-0.14.2",
-    urls = ["https://github.com/bazelbuild/rules_docker/releases/download/v0.14.2/rules_docker-v0.14.2.tar.gz"],
+    sha256 = "6287241e033d247e9da5ff705dd6ef526bac39ae82f3d17de1b69f8cb313f9cd",
+    strip_prefix = "rules_docker-0.14.3",
+    urls = ["https://github.com/bazelbuild/rules_docker/releases/download/v0.14.3/rules_docker-v0.14.3.tar.gz"],
 )
 
 load(
@@ -138,11 +138,11 @@ git_repository(
 
 http_archive(
     name = "bazel_toolchains",
-    sha256 = "a019fbd579ce5aed0239de865b2d8281dbb809efd537bf42e0d366783e8dec65",
-    strip_prefix = "bazel-toolchains-0.29.2",
+    sha256 = "1342f84d4324987f63307eb6a5aac2dff6d27967860a129f5cd40f8f9b6fd7dd",
+    strip_prefix = "bazel-toolchains-2.2.0",
     urls = [
-        "https://mirror.bazel.build/github.com/bazelbuild/bazel-toolchains/archive/0.29.2.tar.gz",
-        "https://github.com/bazelbuild/bazel-toolchains/archive/0.29.2.tar.gz",
+        "https://mirror.bazel.build/github.com/bazelbuild/bazel-toolchains/archive/2.2.0.tar.gz",
+        "https://github.com/bazelbuild/bazel-toolchains/archive/2.2.0.tar.gz",
     ],
 )