Switch to rawgit cdn to serve 7za binaries.
Switch to rawgit cdn to serve 7za binaries.

cf. https://github.com/itchio/7za-binaries

itchio/itch,itchio/itch,itchio/itch,leafo/itchio-app,itchio/itch,itchio/itchio-app,itchio/itchio-app,itchio/itchio-app,leafo/itchio-app,itchio/itch,leafo/itchio-app,itchio/itch