Lucene: Add back the core-and-backward-codecs target

This is needed after the upgrade to Lucene 5.4.1.

This partially reverts commit fc70ea396173a667b13272646997e222bb4d0756.

Change-Id: Ie8f4449a08ff951278863bddf39016a951a05067

gerrit-lucene/BUCK

diff --git a/gerrit-lucene/BUCK b/gerrit-lucene/BUCK
index e9490d0..5a6df97 100644
--- a/gerrit-lucene/BUCK
+++ b/gerrit-lucene/BUCK
@@ -11,7 +11,7 @@
     '//gerrit-server:server',
     '//lib:gwtorm',
     '//lib:guava',
-    '//lib/lucene:lucene-core',
+    '//lib/lucene:lucene-core-and-backward-codecs',
   ],
   visibility = ['PUBLIC'],
 )
@@ -34,7 +34,7 @@
     '//lib/jgit:jgit',
     '//lib/log:api',
     '//lib/lucene:lucene-analyzers-common',
-    '//lib/lucene:lucene-core',
+    '//lib/lucene:lucene-core-and-backward-codecs',
     '//lib/lucene:lucene-misc',
   ],
   visibility = ['PUBLIC'],