Added a README.

Change-Id: I51bc1907d0cf57946263d6ea00ce7a539364b7a2
Reviewed-on: http://review.couchbase.org/7024
Tested-by: Dustin Sallings <dustin@spy.net>
Reviewed-by: Steve Yen <steve.yen@gmail.com>

README.markdown

@@ -0,0 +1,17 @@
+# mccouch
+
+No, not [this mccouch](https://github.com/mccouch), but a memcached
+binary protocol interface to [CouchDB][couchdb].
+
+This is used by Couchbase Server to provide an efficient means of
+moving data between from [ep-engine][epe] and [CouchDB][couchdb].
+
+If you want to build and hack on this, it is recommended to start with
+the [couchdb manifest build][manifest].  That'll get it all together
+for you.
+
+
+[couchdb]: http://couchdb.apache.org/
+[couchbase]: http://www.couchbase.com/
+[epe]: https://github.com/membase/ep-engine
+[manifest]: https://github.com/couchbase/couchdb-manifest