package version metadata for external/

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Change-Id: If688e63d945690a0e24f5653dcc18628c5edcd9c
diff --git a/README.version b/README.version
new file mode 100644
index 0000000..07b8d99
--- /dev/null
+++ b/README.version
@@ -0,0 +1 @@
+URL: http://zserge.com/jsmn.html