API change - `stats` -> `stratum`
[`2e6041d`](https://github.com/SChernykh/p2pool/commit/2e6041dcf5d5fc54182634dc31d68445a3225dd6#diff-4a082cd983adf68c4a2d7297cc57897a3ef9b4c3a1fe7f342957d8196ccc24d7R1312)

This will turn `local/stats` into `local/stratum`?