Add support for Bazel in Gerrit tree build

Change-Id: I7deca1671d2a0e93e755b645cb5561e3f4ac6875

BUILD

diff --git a/BUILD b/BUILD
new file mode 100644
index 0000000..7dc8ff5
--- /dev/null
+++ b/BUILD
@@ -0,0 +1,13 @@
+load("//tools/bzl:plugin.bzl", "gerrit_plugin")
+
+gerrit_plugin(
+    name = "avatars-external",
+    srcs = glob(["src/main/java/**/*.java"]),
+    resources = glob(["src/main/resources/**/*"]),
+    manifest_entries = [
+        "Gerrit-PluginName: avatars-external",
+        "Implementation-Title: External Avatar plugin",
+        "Implementation-URL: https://gerrit-review.googlesource.com/#/admin/projects/plugins/avatars-external",
+        "Gerrit-AvatarProvider: com.googlesource.gerrit.plugins.avatars.external.ExternalUrlAvatarProvider",
+    ],
+)