Add dependency on joda-time

Core gerrit migrated from joda-time to the Java 8 date/time API, and
no longer exports joda-time in the plugin API. As a result, the plugin
cannot be built against the latest snapshot API in standalone mode.

Long term we should migrate the LFS plugin to use the Java 8 APIs,
but as a temporary solution add the dependency to fix the standalone
build.

Change-Id: Ie83cb2be38c4f7440a89eef01d9a9bef3058c7e4
diff --git a/BUILD b/BUILD
index 0bcbd51..7689c5e 100644
--- a/BUILD
+++ b/BUILD
@@ -21,6 +21,7 @@
         "@jgit_http_apache//jar",
         "@jgit_lfs//jar",
         "@jgit_lfs_server//jar",
+        "@joda_time//jar",
     ],
 )
 
diff --git a/external_plugin_deps.bzl b/external_plugin_deps.bzl
index 8b4a6ab..b7601ff 100644
--- a/external_plugin_deps.bzl
+++ b/external_plugin_deps.bzl
@@ -39,3 +39,10 @@
       'plugin.properties',
     ],
   )
+
+  maven_jar(
+    name = 'joda_time',
+    artifact = 'joda-time:joda-time:2.9.9',
+    sha1 = 'f7b520c458572890807d143670c9b24f4de90897',
+  )
+