create importable function for defining zlib

examples/WORKSPACE

diff --git a/examples/WORKSPACE b/examples/WORKSPACE
index 878b255..8b97e47 100644
--- a/examples/WORKSPACE
+++ b/examples/WORKSPACE
@@ -41,18 +41,10 @@
     urls = ["https://github.com/bazelbuild/bazel-skylib/archive/2169ae1c374aab4a09aa90e65efe1a3aad4e279b.tar.gz"],
 )
 
-http_archive(
-    name = "net_zlib",
-    build_file = "//:third_party/zlib.BUILD",
-    sha256 = "c3e5e9fdd5004dcb542feda5ee4f0ff0744628baf8ed2dd5d66f8ca1197cb1a1",
-    strip_prefix = "zlib-1.2.11",
-    urls = ["https://zlib.net/zlib-1.2.11.tar.gz"],
-)
+load("@com_google_protobuf//:protobuf_deps.bzl", "protobuf_deps")
 
-bind(
-    name = "zlib",
-    actual = "@net_zlib//:zlib",
-)
+protobuf_deps()
 
 load("@bazel_skylib//lib:versions.bzl", "versions")
+
 versions.check(minimum_bazel_version = "0.5.4")