Update appveyor rust version
Update appveyor rust version

gwenn/rusqlite,mikelodder7/rusqlcipher,xinghun92/rusqlite,gwenn/rusqlite,xinghun92/rusqlite,mikelodder7/rusqlcipher,mikelodder7/rusqlcipher,jgallagher/rusqlite,jgallagher/rusqlite,xinghun92/rusqlite,gwenn/rusqlite,jgallagher/rusqlite