Fix typo (upgrade is spelled with an r)
Fix typo (upgrade is spelled with an r)

Change-Id: Ibd4ec7a047d8b6ba7d245633c60001ecd80cedc9
Reviewed-on: http://review.couchbase.org/123965
Reviewed-by: Dave Rigby <a09264da4832c7ff1d3bf1608a19f4b870f93750@couchbase.com>
Tested-by: Build Bot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>

daverigby/kv_engine,daverigby/kv_engine,daverigby/kv_engine,daverigby/kv_engine