fix get vs ad_hoc query choice

If you did a query where the only condition was
based on the key it would always try to do a get,
even if the condition was checking against an
array of values.  When it is an array it should
fall back to ad_hoc.

adapters/dm-couchdb-adapter/lib/couchdb_adapter.rb

@@ -201,6 +201,7 @@ def build_request(query)
         elsif query.conditions.length == 1 &&
               query.conditions.first[0] == :eql &&
               query.conditions.first[1].key? &&
+              query.conditions.first[2].length == 1
               !query.conditions.first[2].is_a?(String)
           get_request(query)
         else