Fix name codemirror is cached under

The cache in ~/.gerritcodereview/buck-cache uses the basename of
the -o parameter to store the file. Calling it dist.zip means we
see the entry in the cache as dist.zip-${SHA1}, which is not where
a developer might expect to find codemirror. Use a naming pattern
similar to the Maven artifact case.

Change-Id: I956cb657e02a00124309896de96f449aad8d1b87
diff --git a/lib/codemirror/BUCK b/lib/codemirror/BUCK
index 5d5aaed..0f2d313 100644
--- a/lib/codemirror/BUCK
+++ b/lib/codemirror/BUCK
@@ -14,7 +14,7 @@
     'echo "Manifest-Version: 1.0" >META-INF/MANIFEST.MF',
     'zip -r $OUT *'
   ]),
-  srcs = [genfile('dist.zip')],
+  srcs = [genfile('codemirror-' + VERSION + '.zip')],
   deps = [
     ':download',
     '//lib:LICENSE-codemirror',
@@ -31,5 +31,5 @@
     ' -v ' + SHA1,
   srcs = [],
   deps = ['//tools:download_file'],
-  out = 'dist.zip',
+  out = 'codemirror-' + VERSION + '.zip',
 )