Fix bug when graphite-api call `.fetch()` with 4 arguments, but `GraphouseReader.fetch()` takes only 2
Fix bug when graphite-api call `.fetch()` with 4 arguments, but `GraphouseReader.fetch()` takes only 2

Graphite-api last revision call fetch with 4 args (start_time, end_time, now, requestContext)

yandex/graphouse,yandex/graphouse,yandex/graphouse